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C R M CENTRE DE RECHERCHES MATHÉMATIQUES Annual Report 2012 2013

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Page 1: AnnualReport 2012 2013 · 2014-11-19 · Centrederecherchesmathématiqes The 2012–2013 thematic program at the CRM was a perfectillustrationofthebreadthofitsactivities,since it

CRM

C E N T R ED E R E C H E R C H E SM A T H É M A T I Q U E S

AnnualReport20122013

Page 2: AnnualReport 2012 2013 · 2014-11-19 · Centrederecherchesmathématiqes The 2012–2013 thematic program at the CRM was a perfectillustrationofthebreadthofitsactivities,since it
Page 3: AnnualReport 2012 2013 · 2014-11-19 · Centrederecherchesmathématiqes The 2012–2013 thematic program at the CRM was a perfectillustrationofthebreadthofitsactivities,since it

CRM

C E N T R ED E R E C H E R C H E SM A T H É M A T I Q U E S

AnnualReport20122013

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Centre de recherches mathématiquesUniversité de MontréalC.P. 6128, succ. Centre-villeMontréal, QC H3C 3J7Canada

[email protected]

Also available on the CRM websitehttp://crm.math.ca/docs/docRap_an.shtml.

© Centre de recherches mathématiquesUniversité de Montréal, 2014

ISBN 978-2-921120-51-7

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Contents

Presenting the Annual Report 2012–2013 1

Thematic Program 3Thematic Program of the Year 2012–2013: “Moduli Spaces, Extremality and Global Invariants” and

“Mathematics of Planet Earth 2013” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Aisenstadt Chairholders in 2012–2013: Fedor Bogomolov, David Gabai, Helmut Hofer, and Gang Tian . 5Activities of the Thematic Year . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Past Thematic Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

General Program 19CRM activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Colloquium and Seminar Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Multidisciplinary and Industrial Program 37Activities of the Multidisciplinary and Industrial Program . . . . . . . . . . . . . . . . . . . . . . . . . . 38

CRM Prizes 40CRM–Fields–PIMS Prize 2013 Awarded to Bruce Reed . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41André-Aisenstadt Prize 2013 Awarded to Spyros Alexakis . . . . . . . . . . . . . . . . . . . . . . . . . . 41The CRM–SSC Prize 2013 Awarded to Derek Bingham . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

The CRM Outreach Program 44Mathematics of Planet Earth 2013 — CRM Public Lectures . . . . . . . . . . . . . . . . . . . . . . . . . . 45Mathematics of Planet Earth 2013 — Cross-Canada Series of Lectures . . . . . . . . . . . . . . . . . . . 48Grandes Conférences du CRM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

CRM Partnerships 52CRM Partners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Joint Initiatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Mathematical Education 57Institut des sciences mathématiques (ISM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Other Joint Initiatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Research Laboratories 61Applied Mathematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62CICMA — Centre Interuniversitaire en Calcul Mathématique Algébrique . . . . . . . . . . . . . . . . . 63CIRGET — Centre Interuniversitaire de Recherches en Géométrie et Topologie . . . . . . . . . . . . . . 64GIREF — Groupe Interdisciplinaire de Recherche en Éléments Finis . . . . . . . . . . . . . . . . . . . . . 66LaCIM — Laboratoire de Combinatoire et d’Informatique Mathématique . . . . . . . . . . . . . . . . . . 67Mathematical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Mathematical Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71PhysNum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Publications 76Recent Titles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Previous Titles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Scientific Personnel 82CRM Members in 2012–2013 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Postdoctoral Fellows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

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Visitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

List of Students Having Graduated in 2012–2013 88Ph.D. Students . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89M.Sc. Students . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Governance and Scientific Guidance 95Board of Directors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96Committee of Directors of Laboratories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96International Scientific Advisory Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

CRM Administrative and Support Staff 102The Director’s Office . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103Scientific Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103Computer Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Mandate of the CRM 104

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Presenting the Annual Report 2012–2013

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The 2012–2013 thematic program at the CRM was aperfect illustration of the breadth of its activities, sinceit included a Thematic Year on Moduli Spaces, Ex-tremality and Global Invariants as well as the The-matic Year “Mathematics of Planet Earth 2013”. Thusboth pure and interdisciplinary mathematics were fea-tured at the CRM this year. The Thematic Year on Mod-uli Spaces, Extremality and Global Invariants was ded-icated to questions that lie at the heart of the cur-rent research in geometry. It consisted of eight re-search workshops (paired with mini-courses) and se-ries of Aisenstadt lectures by Fedor Bogomolov, DavidGabai, Helmut Hofer, and Gang Tian, respectively. Iwould like to express my thanks to the members of theThematic Year scientific committee: Vestislav Apos-tolov, Steven Boyer, Virginie Charette, Olivier Collin,Octav Cornea, Jacques Hurtubise, François Lalonde,Steven Lu, Frédéric Rochon, Peter Russell, and Jo-hannes Walcher.

The Mathematics of Planet Earth program, launchedby Christiane Rousseau during her mandate as CRMdirector, was enthusiastically adopted by our Cana-dian partners and many mathematics research insti-tutes across the globe. In particular the Mathematics ofPlanet Earth 2013 (MPE 2013) program was a joint ini-tiative of Canadian institutions, with activities takingplace in many locations. The goal of this thematic pro-gram was to tackle pressing and emerging challengesin population and ecosystem health, including the con-trol of major transmissible diseases, the optimizationand monitoring of vaccination, the impact of climatechange on invasive species, the protection of biodiver-sity, and the sustainable management of ecosystems.The MPE 2013 year featured three summer schools forgraduate students and postdoctoral fellows as well asworkshops that took place at the CRM, the Fields In-stitute (in Toronto), the PIMS (in Edmonton), St. John’s(under the auspices of AARMS), and BIRS. The sci-entific committee of the Canadian program includedJacques Bélair, Mark Lewis, Frithjof Lutscher, JamesWatmough, and Jianhong Wu.

The CRM is also proud of the outstanding re-searchers who were awarded its prizes this year: BruceReed from McGill University (CRM–Fields–PIMS Prize2013), Spyros Alexakis from the University of Toronto

(André-Aisenstadt Prize 2013), and Derek Binghamfrom Simon Fraser University (CRM–SSC Prize 2013).The public lectures that took place at the CRM in 2012–2013 were especially brilliant. Four of these were re-lated to the MPE 2013 Thematic Year. The lectures byIngrid Daubechies and Paul Embrechts were part ofthe MPE 2013 – CRM Public Lectures Series; the lec-ture by Professor Daubechies was actually sponsoredby the prestigious Simons Foundation. The lectures byNilima Nigam and Anthony Peirce were part of theMPE 2013 – Cross-Canada Series of Public Lectures.The fifth public lecture was given by the French physi-cist Alain Aspect and was part of the Grandes Con-férences series.

An Unité Mixte Internationale (UMI) was establishedby the CNRS at the CRM in 2011 and has givenan impetus to the exchanges between the CRM andthe French mathematical community: sixteen Frenchmathematicians visited the CRM and three Montréalresearchers visited colleagues in France in 2012-2013thanks to the UMI. Also in 2012-2013, the relationshipbetween the CRM and the French mathematical com-munity led to the organization of two colloquia withinthe Entretiens Jacques-Cartier (in Lyon): a colloquiumon risk management and a colloquium on mathemati-cal physics.

The activities of the CRM are supported by the Gov-ernment of Canada through NSERC, the Governmentof Québec through FRQNT, the Government of theUnited States through the National Science Foundation(NSF), the Mprime network, and its partner univer-sities: the Université de Montréal, McGill University,the Université du Québec à Montréal, Concordia Uni-versity, the Université Laval, the Université de Sher-brooke, and the University of Ottawa. The Society forMathematical Biology (SMB) provided support to stu-dents and young (particularly pre-tenure) investiga-tors participating in the MPE 2013 program. On behalfof the CRM I extend my sincere thanks to all our part-ners, who help the CRM develop its activities within aworld-class research program in the mathematical sci-ences.

Luc Vinet, DirectorCentre de recherches mathématiques (CRM)

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Thematic Program

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Thematic Programs of the Year 2012–2013“Moduli Spaces, Extremality and Global Invariants” and “Mathematics ofPlanet Earth 2013”Moduli Spaces, Extremality and GlobalInvariants

Geometry in the large sense, and especially the ge-ometry of the most natural and simple structures onmanifolds, is going through a golden age. More thanever, we are close to a satisfactory understanding of thebasic blocks that constitute the most intricate spaces,be they Riemannian, complex, algebraic, symplectic ordynamical. Contemplating this development, one seesthe ubiquitous role played by extremality and stabil-ity understood in various contexts: the proof of thePoincaré conjecture and the parabolic methods thatreach minimality in low-dimensional manifolds placeus roughly at the point where mathematicians were atthe end of the nineteenth century when one had toinvent, beyond the analytical method of uniformiza-tion, a full topological theory needed to achieve a sat-isfactory classification. Minimality and extremality arealso present in higher dimensions, both in the Kähler–Einstein case and in the constant scalar curvature Käh-ler case, where Aubin, Yau, Tian and Donaldson estab-lished basic existence theorems.

Extremality is also behind the recent spectacular proofby Taubes of the full Weinstein conjecture on the exis-tence of closed orbits of the Reeb flow on contact man-ifolds. Although his proof relies on a subtle interplaybetween the contravariant Seiberg–Witten theory andthe covariant embedded contact homology, the conjec-ture itself and ultimately the idea of its proof rely onthe minimality of an action associated to some closedtrajectory that can also be computed as a capacity. Insymplectic topology and geometry, the progress overthe last decade is remarkable on almost all importantquestions: while relative symplectic field theory, con-sidered by some mathematicians to be the ultimate the-ory of classical and quantum mechanics, is developingquickly with tools coming from several parts of math-ematics (analytical foundations, algebraic formalism,geometric intuition and setting), advances on all as-pects of the ubiquitous Floer theory are now percolat-ing in 3 and 4-dimensional manifolds. Almost indepen-dently, the theory of J-holomorphic curves has beenused to derive real enumerative invariants, opening forthe first time the field of enumerative real algebraic ge-

ometry that had, until then, stagnated since its infancyalmost two centuries ago.

Moduli spaces are present everywhere: the spaces ofmetrics, be they Kähler or almost Kähler, the spaceof almost complex structures, the space of represen-tations of the fundamental group of surfaces or 3-folds in suitable Lie groups and the so-called higherTeichmüller spaces, the Hamiltonian diffeomorphismgroup over which the Hofer norm is given, the spaceof configurations of the so-called clusters, a sort ofdual to the Fukaya A-structure, the space of pseudo-algebraic functions on algebraic curves that are myste-riously connected to integrable systems, random ma-trices, Gromov–Witten-invariants, all of these spacesare currently attracting the attention of the mathemat-ical community more than ever before, with an inter-disciplinary perspective that is now, clearly, essential.

The theme year on “Moduli Spaces, Extremality andGlobal Invariants” was a hub dedicated to the studyof these questions, which lie at the heart of the cur-rent developments in geometry. The program con-sisted of eight research workshops paired with mini-courses and several series of Aisenstadt lectures, all co-ordinated to maximize constructive interactions. Theprogram also supported a number of research visi-tors and postdoctoral fellows so that they could workat CIRGET, the geometry-topology research labora-tory of the CRM. The scientific committee of theyear included the following researchers: VestislavApostolov (UQAM), Steven Boyer (UQAM), VirginieCharette (Sherbrooke), Olivier Collin (UQAM), Oc-tav Cornea (Montréal), Jacques Hurtubise (McGill),François Lalonde (Montréal), Steven Lu (UQAM),Frédéric Rochon (UQAM & ANU), Peter Russell(McGill), Johannes Walcher (McGill). The organizers ofthe semester are very grateful to the National ScienceFoundation for its financial support.

Mathematics of Planet Earth 2013

As part of the Mathematics of Planet Earth 2013(MPE 2013) initiative, a series of workshops and sum-mer schools was organized in 2013, consisting of activi-ties taking place across Canada. The challenges that weface on our planet are becoming increasingly complex

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Thematic Program

since ecological, economic and social systems are largeintertwined networks governed by dynamic processesand feedback loops. Mathematical models are indis-pensable in understanding and managing such sys-tems because they provide insight into governing pro-cesses; they help predict future behaviour; and they al-low for risk-free evaluation of possible interventions.The goal of this thematic program was to tackle press-ing and emerging challenges in population and ecosys-tem health, including the understanding and control-ling of major transmissible diseases, the optimizingand monitoring of vaccination, the prediction of theimpacts of climate change on invasive species, the pro-tection of biodiversity, and the sustainable manage-ment of ecosystems.

This pan-Canadian program brought together the in-ternational community of researchers who work onthese topics in a series of workshops fostering ex-

change and stimulating cross-disciplinary research be-tween all scientific areas involved. Three summerschools introduced graduate students and postdoctoralfellows to the art of modelling living systems and to thelatest tools and techniques for analyzing these mod-els. These activities took place not only at the CRM inMontréal, but also at the Fields Institute in Toronto, atthe PIMS in Edmonton, at St. John’s under the auspicesof AARMS, and at BIRS. The scientific committee of theCanadian program included Jacques Bélair (Univer-sité de Montréal), Mark Lewis (University of Alberta),Frithjof Lutscher (University of Ottawa), James Wat-mough (University of New Brunswick), and JianhongWu (York University). The National Science Founda-tion (NSF) and the Society for Mathematical Biology(SMB) provided funding in order to support studentsand young (particularly pre-tenure) investigators par-ticipating in this program.

Aisenstadt Chairholders in 2012–2013Fedor Bogomolov, David Gabai, Helmut Hofer, and Gang Tian

Fedor Bogomolov

Professor Fedor Bogomolov is an outstanding mathe-matician renowned for his work in algebraic geometryand number theory. He graduated from the Faculty ofMechanics and Mathematics of the Moscow State Uni-versity and earned his doctorate at the Steklov Institutein 1973. F. Bogomolov obtained his habilitation in 1983and became a full professor at the Courant Institutein 1994. He has conducted seminal work on the geom-etry of Kähler manifolds, Calabi–Yau manifolds, mir-ror symmetry, holomorphic vector bundles, and theapproach of diophantine equations through the geom-etry of hyperbolic manifolds and dynamical systems.We refer the reader to the Spring 2013 edition of theBulletin du CRM for a description of Bogomolov’s lec-tures, respectively entitled• External and Internal Symmetries and their Role in

Mathematics and Nature;• Universal Spaces in Birational Algebraic Geometry;

and• Several Aspects of Infinite Transitivity.

David Gabaiby Steven Boyer (UQAM)

Professor David Gabai of Princeton University gavea series of four lectures during the events surround-ing the workshop The Topology of 3-dimensional man-ifolds. Professor Gabai is a world leader in the topol-ogy and geometry of low-dimensional manifolds, withmany outstanding research contributions throughouta career in which he has solved major problems and de-veloped powerful techniques that have had a profoundimpact in the field. These include proofs of the Seifertfiber space conjecture (1992), the rigidity of homotopyhyperbolic 3-manifolds (1994), the Smale Conjecturefor hyperbolic 3-manifolds (2001), and Marden’s Tame-ness Conjecture (2006). He was awarded the OswaldVeblen Prize in Geometry by the American Mathemat-ical Society in 2004, and was made a member of theAmerican National Academy of Sciences in 2012.

Professor Gabai’s first two lectures were expository innature. The first provided an overview of Poincaré’smany contributions to topology, remarkable for theirfoundational and seminal nature as well as their im-pact on subsequent research. The second surveyed thestill mysterious field of the volumes of hyperbolic 3-manifolds from W. Thurston’s 1970s proof that the setof such positive real numbers is closed and well or-dered, to Professor Gabai’s 2009 theorem with RobertMeyerhoff and Nathaniel Thurston that the Weeks

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manifold is the unique manifold to realize the mini-mal possible volume among closed orientable hyper-bolic 3-manifolds. He described the three decades ofeffort by many mathematicians, using a wide vari-ety of techniques, that bridged these results, includ-ing the use of Ricci flow by Ian Agol and Nathan Dun-field to obtain strong volume estimates. The talk con-cluded with a discussion of open problems and an ap-proach for addressing the Thurston, Weeks, Matveev–Fomenko conjecture that complete low-volume hyper-bolic 3-manifolds are of low topological complexity.

Professor Gabai’s last two Aisenstadt Chair lectures fo-cused on the topology of the ending lamination spaceassociated to a finite type hyperbolic surface S. He setthe stage by describing its connections with the spaceof projective measured laminations of S, the Gromovboundary of the curve complex ofS, and the set of dou-bly degenerate hyperbolic structures on S × R. Mostof his time was devoted, though, to explaining his re-cent results in the area. For instance, if S has genus gand p punctures, then its ending lamination space isboth (n− 1)-connected and (n− 1)-locally-connectedwhere 2n+ 1 = 6g + 2p− 7. Further, when g is zero,its ending lamination space is the Nöbeling space ofpoints in R2m+1 with at most m rational coordinates.

Helmut Hoferby Octav Cornea (Université de Montréal)

Helmut Hofer obtained his Ph.D. at the University ofZürich in 1981 and is currently a permanent member ofthe Institute for Advanced Study in Princeton. Amongother prestigious distinctions, he is a member of theNational Academy of Sciences and was twice an in-vited speaker at an International Congress of Mathe-maticians (the second time, in 1998, he was actually aplenary speaker). Hofer is one of the founders of mod-ern symplectic topology. His work, alone and with col-laborators, on Floer theory, on capacities and applica-tions to Hamiltonian dynamics, and on cases of theWeinstein conjecture in dimension three was trans-formational. It led to the establishment and the fur-ther study by countless researchers of (what is nowcalled) the Hofer geometry of the Hamiltonian dif-feomorphisms groups. More recently, together withWysocki and Zehnder he is developing polyfold the-ory, a wide-reaching extension of usual differential ge-ometry particularly adapted to the study of regularityproperties of moduli spaces of solutions of PDEs.

The topic of Hofer’s talks was Hamiltonian Dynamicsand Symplectic Rigidity. Hamiltonian systems, whichoccur frequently in physics, are also of great interestin many branches of mathematics. Symplectic geome-try allows us to formulate certain dynamical questionsinto geometric and, sometimes, even algebraic prob-lems. This is based on the properties of the modulispaces of (perturbed) J-holomorphic curves that nat-urally arise in relation to a given Hamiltonian sys-tem, once the appropriate action functional is defined.Assuming that these moduli spaces are well-behaved,they are amenable to combinatorial assembly and theoutput is presented as certain homological type in-variants such as Gromov–Witten invariants, Floer ho-mology, and others. Understanding of these invariantssheds light on the dynamical properties of the initialHamiltonian system. In the last twenty years the sym-plectic machinery that follows this general scheme hasdeveloped tremendously. Hofer’s talks reviewed partof these developments, and emphasized that the timehas come for a renewed exploration of questions origi-nating in celestial mechanics and space transportationby using all the sophisticated tools at our disposal to-day.

Gang Tianby Vestislav Apostolov (UQAM)

Professor Gang Tian, who is Eugene Higgins Profes-sor at Princeton and the director of the Beijing Inter-national Centre for Mathematical Research (BICMR),gave a series of three Aisenstadt lectures during theworkshop Extremal Kähler metrics. In global analysisand geometry over the last 25 years, Professor GangTian has been one of the most influential and versatilefigures. From his Ph.D. thesis to his most recent work,his contributions have been distinguished by their di-versity and depth. His most striking work to date con-cerns the existence of Kähler–Einstein metrics on com-plex manifolds (which was a main theme of the work-shop), but he has made many other significant con-tributions. For instance, he established (with Y. Ruan)the associativity of the quantum cohomology ring ofa symplectic manifold, constructed (with Jun Li) mod-uli spaces of curves in algebraic symplectic geometry,elaborated (with J. Morgan) a clear and detailed expo-sition of Perelman’s proof of the Poincaré conjecture,and developed ideas to link Kähler–Ricci flow with theMori program in algebraic geometry.

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Most relevant to this CRM workshop, however, isTian’s work on Kähler–Einstein metrics. In his earlycareer, he solved the existence question for Kähler–Einstein metrics on compact complex surfaces withpositive first Chern class, and showed that Fano va-rieties with a Kähler–Einstein metric must be stable inthe sense of geometric invariant theory, thus confirm-ing part of a suggested correspondence by Yau. Pro-fessor Tian gave a precise formulation of this corre-spondence, known today as the Yau–Tian–Donaldsonconjecture, identifying the obstruction to the existenceof Kähler–Einstein metrics with what is now calledthe K-stability of the Fano variety. His ideas have in-spired a tremendous amount of work in recent years,and spectacular progress has been made, culminatingin the complete resolution of the conjecture by Tianhimself, and by Xiuxiong Chen, Simon Donaldson andSong Sun.

Professor Tian’s first lecture was expository in nature,and reviewed the theory and latest progress related tothe existence of Kähler–Einstein metrics. The secondlecture was concerned with a more detailed expositionof the key ideas of Professor’s Tian most recent workregarding the existence of Kähler–Einstein metrics ona K-stable Fano variety. The third lecture featured re-cent results on convergence of the Kähler–Ricci flow on a Fano variety.

Aisenstadt Chair

The Aisenstadt chair was endowed by Montréal phi-lanthropist Dr. André Aisenstadt. Under its auspices,

one or more distinguished mathematicians are invitedeach year for a period of at least one week, ide-ally one or two months. During their stay the lec-turers present a series of lectures on a specializedtopic. They are also invited to prepare a monograph(see the chapter on publications in the present re-port for a list of these monographs). At the requestof Dr. Aisenstadt, the first lecture given by an Aisen-stadt chairholder should be accessible to a wide au-dience. Previous holders of the Aisenstadt chair are:Marc Kac, Eduardo Zarantonello, Robert Hermann,Marcos Moshinsky, Sybren de Groot, Donald Knuth,Jacques-Louis Lions, R. Tyrrell Rockafellar, YuvalNe’eman, Gian-Carlo Rota, Laurent Schwartz, GérardDebreu, Philip Holmes, Ronald Graham, Robert Lang-lands, Yuri Manin, Jerrold Marsden, Dan Voiculescu,James Arthur, Eugene B. Dynkin, David P. Ruelle,Robert Bryant, Blaine Lawson, Yves Meyer, Ioan-nis Karatzas, László Babai, Efim I. Zelmanov, PeterHall, Sir David Cox, Frans Oort, Joel S. Feldman, Ro-man Jackiw, Duong H. Phong, Michael S. Waterman,Arthur T. Winfree, Edward Frenkel, Laurent Lafforgue,George Lusztig, László Lovász, Endre Szemerédi, Pe-ter Sarnak, Shing-Tung Yau, Thomas Yizhao Hou, An-drew J. Majda, Manjul Bhargava, K. Soundararajan,Terence Tao, Noga Alon, Paul Seymour, Richard Stan-ley, John J. Tyson, John Rinzel, Gerhard Huisken, Jean-Christophe Yoccoz, Wendelin Werner, Andrei Ok-ounkov, Svante Janson, Craig Tracy, Stéphane Mal-lat, Claude Le Bris, Akshay Venkatesh, Yuri Gurevich,Angus Macintyre, Alexander Razborov, James Robins,John Preskill, Renato Renner, László Erdős, Elon Lin-denstrauss, Richard M. Schoen.

Activities of the Thematic Year

The reports are presented in the language in which they were submitted. As far as MPE 2013 is concerned, wehave given the list of all the activities taking place in Canada but included reports only for the CRM activities.

WorkshopSpectral Invariants on Non-Compact andSingular SpacesJuly 23–27, 2012, CRMSponsored by the CRM, the NSF, and the AustralianNational University

Organizers:Pierre Albin (UI Urbana-Champaign), Frédéric Rochon(UQAM & ANU)

Speakers:Spyros Alexakis (Toronto), Dean Baskin (Northwest-ern), Jean-Michel Bismut (Paris-Sud), David Borthwick(Emory), Maxim Braverman (Northeastern), JochenBrüning (Humboldt), Tanya Christiansen (Missouri),Xianzhe Dai (UC Santa Barbara), Kiril Datchev (MIT),Daniel Grieser (Oldenburg), Colin Guillarmou (ÉNS),Chris Kottke (Brown), Zhiqin Lu (UC Irvine), Xi-aonan Ma (Paris Diderot), Jeremy Marzuola (UNC—Chapel Hill), Richard Melrose (MIT), Gerardo Mendoza

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(Temple), Jinsung Park (KIAS), Bert-Wolfgang Schulze(Potsdam), Michael Singer (Univ. Coll. London), Gun-ther Uhlmann (Washington), Mathai Varghese (Ade-laide), András Vasy (Stanford), Siye Wu (Hong Kong),Jared Wunsch (Northwestern), Ken-Ichi Yoshikawa(Kyoto), Steve Zelditch (Northwestern)Number of participants: 44Le premier atelier de l’année thématique a eu lieu auCRM du 23 au 27 juillet, 2012. Les organisateurs étaientPierre Albin (Urbana-Champaign) et Frédéric Rochon(UQAM). Il y avait entre 5 et 6 exposés par jour, pour untotal de 25 exposés. Les exposés étaient de 50 minutes,ce qui a donné suffisamment de temps à chaque con-férencier pour présenter ses résultats, donner une idéedes méthodes utilisées et mentionner des questions ou-vertes. Même si l’horaire était assez rempli, les partici-pants ont aussi eu plusieurs occasions d’échanger, no-tamment durant les pauses-café et sur l’heure du lunch.

Un mélange intéressant de sujets a été abordé. Cer-tains exposés portaient sur la théorie de l’indice (ceuxde Wu, Varghese, Brüning et Kottke) ou sur des in-variants spectraux apparentés tels l’invariant êta etla torsion analytique (Melrose, Park, Ma, Yoshikawaet Dai). D’autres portaient plutôt sur la théorie dela diffusion, notamment les exposés de Christiansen,Bortwick, Baskin, Vasy, Datchev, Guillarmou, ou plusgénéralement sur l’analyse spectrale, comme dans lesexposés de Lu, Marzuola, Wunsch et Grieser. Cer-tains résultats touchant à la géométrie complexe ontété abordés dans les exposés de Mendoza et Singer.Enfin, certains sujets étaient plus spécialisés, commel’exposé de Jean-Michel Bismut sur le Laplacien hy-poelliptique ou l’exposé de Spyros Alexakis utilisantl’analyse non linéaire. Plusieurs conférenciers ont ac-cepté de partager leurs transparents et ces dernierssont disponibles sur la page web de l’atelier.

Un des beaux moments de l’atelier est sans doutel’exposé de Jared Wunsch, qui a expliqué avec unegrande clarté son résultat le plus récent obtenu avecDean Baskin. D’ailleurs, en collaboration avec unautre participant de l’atelier, Jeremy Marzuola, ils ontl’intention d’écrire un article utilisant leur résultatpour obtenir une estimation de Strichartz globale surdes domaines extérieurs à des polygones.

En collaboration avec un autre atelier du CRM, celuide juin 2012 portant sur la géométrie des valeurs pro-pres et fonctions propres, nous projetons de publier desactes de conférence. Plusieurs participants se sont déjà

montrés intéressés à apporter leur contribution, ce quidevrait mener à un ouvrage intéressant.

Mini-course & WorkshopThe Topology of Algebraic VarietiesSeptember 21–28, 2012, CRMSponsored by the CRM and the NSF

Organizers:Rajendra Gurjar (Tata Inst.), Shulim Kaliman (Miami),Steven Lu (UQAM), Peter Russell (McGill)Lecturers:Ryoichi Kobayashi (Nagoya), Adrian Langer (War-saw), Terrence Napier (Lehigh), Walter Neumann(Columbia), Anne Pichon (Aix-Marseille), Mohan Ra-machandran (Buffalo)Speakers:Shreeram Abhyankar (Purdue), Donu Arapura (Pur-due), Fedor Bogomolov (Courant Inst.), Frédéric BrunoCampana (Henri Poincaré), Fabrizio Catanese (Bay-reuth), Bruno de Oliveira (Miami), Philippe Eyssi-dieux (Joseph Fourier), Hubert Flenner (Bochum), Lud-mil Katzarkov (Miami), JongHae Keum (KIAS), Ry-oichi Kobayashi (Nagoya), Mariusz Koras (Warsaw),Frank Kutzschebauch (Bern), Adrian Langer, MichaelMcQuillan (IHÉS), Masayoshi Miyanishi (KwanseiGakuin), Terrence Napier, Madhav Nori (Chicago),Bangere Purnaprajna (Kansas), Mohan Ramachandran,Sheng-Li Tan (East China NU), Jörg Winkelmann (Bo-chum)Number of participants: 68Friday September 21 and the following weekend wereoccupied by three mini-courses of four lectures each.The first mini-course, on topological methods in thestudy of singularities (by Anne Pichon and WalterNeumann) was perhaps the most accessible for theaudience, which included many postdoctoral fellowsand graduate students. Starting with classical resultson the topology of isolated singularities (Milnor fi-bration, iterated torus links, Puiseux expansions), thespeakers introduced the concept of metrically con-vex singularity, the new Thick–Thin decomposition,Carousel structure, and applications to Lipschitz ge-ometry of isolated singularities. The lecturers (Ter-rence Napier and Mohan Ramachandran) of the sec-ond mini-course discussed the geometry of noncom-pact Kähler manifolds and the structure theorem forthese objects (in particular they described conditionsunder which such a manifold admits a proper holomor-phic map onto a Riemann surface). In the third mini-

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course, Adrian Langer concentrated on the generaliza-tion of the Bogomolov–Miyaoka–Yau inequality to sin-gular quasiprojective varieties, while R. Kobayashi dis-cussed the modern approach to Nevanlinna theory thathe introduced and that was motivated by the BMY in-equality.

The workshop lectures started on Monday, Septem-ber 24. Among these there were several strong reportsincluding solutions of old problems. We mention afew: M. Koras presented an idea of a solution of theCoolidge–Nagata conjecture stating that any plane ra-tional curve with locally irreducible singularities canbe rectified by birational automorphisms of the plane;F. Kutzschebauch gave a sketch of the solution of theGromov–Vaserstein problem (via Gromov’s h-princi-ple); J. Keum lectured on the algebraic version of theMontgomery–Yang problem (as suggested by J. Kollar);in L. Katzarkov’s lecture, phantoms of derived cate-gories were used as a new invariant that allows to shownonrationality of a variety even in the case when theintermediate Jacobian does not work; F. Canatese ex-plained new results on moduli space of curves whoseautomorphism groups contain a given finite group;H. Flenner, reporting on joint work with S. Kalimanand M. Zaidenberg, presented a definitive result ondeformations of affine surfaces with an A1-fibration;B. Purnaprajna reported on joint work with R. Gurjaron the fundamental groups of surfaces with finite au-tomorphism groups, which leads to a solution of theShafarevich conjecture for certain interesting classesof surfaces; F. Campana explained his joint work withJ. Winkelmann on an attempt to relate special varietiesto varieties that satisfy the h-principle, the so-calledOka varieties; M. McQuillan explained his solution ofLang’s conjecture concerning holomorphic curves insurfaces of general type (which improved upon theChern inequality bound of Bogomolov).

In a lecture liberally annotated with historical reminis-cences, S. S. Abhyankar reported on new results on lo-cal fundamental groups and Galois theory, results thathave their origin in his papers on this subject in theAmerican Journal of Mathematics in 1955 and 1956.His talk, in retrospect, had a special poignancy sincesadly Professor Abhyankar passed away not long afterthe conference.

WorkshopHigher Teichmüller–Thurston TheoryOctober 15–19, 2012, CRMSponsored by the CRM and the GEAR Network

Organizers:Virginie Charette (Sherbrooke), William M. Gold-man (Maryland), François Labourie (Paris-Sud), AnnaWienhard (Princeton)Speakers:Thierry Barbot (Avignon), Ara Basmajian (GraduateCtr., CUNY & Hunter Coll., CUNY), Martin Bridgeman(Boston Coll.), Suhyoung Choi (KAIST), Jeffrey Dan-ciger (UT Austin), Todd A. Drumm (Howard), VivekaErlandsson (Graduate Ctr., CUNY), William M. Gold-man, François Guéritaud (Lille 1), Tobias Hartnick(Technion), Fanny Kassel (CNRS Lille 1), Steven Ker-ckhoff (Stanford), Youngju Kim (KIAS), Evelyn Lamb,Sean Lawton (Texas-Pan American), Brice Loustau(Paris-Sud), Sara Maloni (Paris-Sud), Karin Melnick(Maryland), Clara Rossi Salvemini (Avignon), Ser PeowTan (NU Singapore), Michael Wolf (Rice)Number of participants: 34La théorie supérieure de Teichmüller-Thurston traitenotamment d’espaces de déformations de structuresgéométriques localement homogènes, de représenta-tions de groupes fondamentaux de surfaces, et de con-nections plates. L’atelier s’est concentré sur les aspectsliés aux métriques lorentziennes conformément plates,les structures géométriques issues de représentationsd’Anosov, ainsi que la géométrie des composantes deHitchin, laquelle généralise celle de Weil-Petersson surl’espace de Teichmüller.

Des présentations ont notamment porté sur lamétrique de pression sur les représentations deHitchin, les variétés modelées sur l’espace anti-De Sit-ter, ainsi que les variétés lorentziennes plates. Nousavons aussi pu profiter de présentations portant surdes sujets plus proches de la théorie de Teichmüllerclassique, tels que les représentations quasi fuchsi-ennes, ainsi que la géométrie lorentzienne.

Il y avait une trentaine de participants, en prove-nance de plusieurs pays: Canada, États-Unis, France,Corée et Singapour. Soulignons que plusieurs jeu-nes chercheurs, chercheurs postdoctoraux et étudiantsgradués, ont eu l’occasion de présenter leurs résultatspendant l’atelier. Nous avons privilégié une formule oùil y avait relativement peu de présentations (au plus six

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par jour), afin que les gens aient le temps de parler deleurs travaux et d’échanger informellement.

Nous pouvons dire que l’atelier a été un franc succès.Nous avons reçu plusieurs courriels de remerciementset de félicitations pour l’atelier. Les gens ont appréciéla taille de l’atelier: comme nous n’étions que trenteparticipants dans des domaines adjacents, nous pou-vions échanger aisément entre nous. C’est pour cetteraison que l’atelier a sans doute favorisé l’émergencede nouvelles collaborations.

WorkshopDisease Dynamics 2013: Immunization, atrue multi-scale problemJanuary 17–19, 2013, PIMSSponsored by PIMS, Mitacs, and Mathematics of PlanetEarth 2013

Organizers:Jessica Conway (Los Alamos Natl. Lab.), Dan Coombs(UBC), Rafael Meza (Michigan)Speakers:Rustom Antia (Emory), Dennis Chao (Fred Hutchi-son Cancer Res. Ctr.), Miles Davenport (New SouthWales), Elamin Elbasha (Merck Res. Labs.), Jane Hef-fernan (York), Katia Koelle (Duke), Jan Medlock (Clem-son), David Patrick (UBC), Alan Perelson (Los AlamosNatl. Lab.), Timothy Reluga (Penn State), Jamie K. Scott(Simon Fraser), David P. Wilson (New South Wales)

WorkshopModels and Methods in Ecology andEpidemiologyFebruary 13–15, 2013, CRMSponsored by the CRM and the Society of Mathemati-cal Biology

Organizers:Jacques Bélair (Montréal), Jianhong Wu (York)Speakers:Madhur Anand (Guelph), Tamara Awerbuch (Har-vard), Christopher Bauch (Guelph), Lydia Bourouiba(MIT), David L. Buckeridge (McGill), David A. Camp-bell (Simon Fraser), Frédéric Guichard (McGill), Jo-han A. P. Heesterbeek (Utrecht), Patrick Leighton(Montréal), Subhash R. Lele (Alberta), Rongsong Liu(Wyoming), Bernard Moulin (Laval), Calistus Ngong-hala (Tennessee), Nicholas Hume Ogden (Montréal),John Takekawa (U.S. Geological Survey), Jianhong Wu(York), Huaiping Zhu (York)

Number of participants: 31In epidemiology and ecology, models are typicallydeveloped along one of two directions: directlyfrom available data, incorporating as many empiricalrecords as possible, or conceptually as dynamical sys-tems, incorporating data via estimation of parameters.The means of investigation for these model classesare quite distinct, and an important methodologi-cal problem is the reconciliation of a priori method-independent issues when they are described in differ-ent terms.

The two main objectives of this workshop were to• start the interactions for the Thematic Year, by

breaking community/network barriers between thepractitioners of different modelling techniques andapproaches, and

• follow up on activities held at the CRM on relatedtopics in the recent past (on Statistical Methods, inMarch 2007 and March 2010, respectively).

A non-exclusive emphasis has been put on zoonoticdiseases, given the concentrated expertise at the Uni-versité de Montréal, through the Faculté de MédecineVétérinaire, and the significance and novelty of theproblems they entail.

The sessions of this three-day workshop correspondedto the different technical approaches in modelling: dy-namical systems with parameter estimation includ-ing variability; empirical models (some based on ge-ographical information systems) of zoonotic diseases;and methodological issues in surveillance and data in-corporation in epidemiological models.

WorkshopEstablishing the scientific foundation forQuantitative Public HealthDecision-MakingApril 29–30, 2013, Fields Institute for Research inMathematical SciencesSponsored by the Fields Institute for Research in Math-ematical Sciences, Mprime, and Mathematics of PlanetEarth 2013

Organizers:David Buckeridge (McGill), Charmaine Dean (WesternOntario) Jianhong Wu (York)Speakers:Amy Greer (PHAC), Sarah Henderson (BCCDC), FranJamieson (PHO), Hedy Jiang (Toronto), Andre Kush-niruk (Victoria), Seyed Moghadas (York), Trisalyn Nel-

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son (Victoria), Beate Sander (PHO), Cécile Tremblay(INSPQ)Number of participants: 42

WorkshopJ-Holomorphic Curves in SymplecticGeometry, Topology and DynamicsApril 29–May 10, 2013, CRM

Organizers:Denis Auroux (UC Berkeley), Octav Cornea (Mont-réal), Yael Karshon (Toronto), François Lalonde (Mont-réal), Leonid Polterovich (Tel Aviv)Speakers:Mohammed Abouzaid (Columbia), Paul Biran (ETHZürich), Strom Borman (Chicago), Lev Buhovsky (TelAviv), Olguta Buse (IUPUI), Tobias Ekholm (Uppsala),Yakov Eliashberg (Stanford), Michael Entov (Tech-nion), Urs Frauenfelder (Seoul NU), Kenji Fukaya (Ky-oto), Sheel Ganatra (Stanford), Basak Gürel (Van-derbilt), Richard Hind (Notre Dame), Ko Honda(Southern California), Michael Hutchings (UC Berke-ley), Michael Khanevsky (Chicago), Siu-Cheong Lau(Harvard), Robert Lipshitz (Columbia), Chiu-Chu Liu(Columbia), Dusa McDuff (Columbia), David Nadler(UC Berkeley), Alexandru Oancea (UPMC), Tim Pe-rutz (UT Austin), Sheila Sandon (Nantes), Felix Schlenk(Neuchâtel), Paul Seidel (MIT), Nicholas Sheridan(IAS), Jake Solomon (Hebrew), Susan Tolman (UIUrbana-Champaign), Michael Usher (Georgia), KatrinWehrheim (MIT), Jean-Yves Welschinger (Lyon 1),Christopher Woodward (Rutgers)Number of participants: 98This workshop consisted of 38 one-hour lectures, in-cluding three series of three one-hour lectures (oneof which was the Aisenstadt Chair series delivered byHelmut Hofer). The other two minicourses were givenby Abouzaid and Sandon, respectively. There are threedifferent aspects of this workshop that made it a verysuccessful and productive meeting:

1. High quality talks on the hottest topics in the sub-ject:• Breakthroughs in classical problems were described

in talks of Buse and Hind (who proved a remark-able form of packing stability), Seidel who de-scribed a new approach to multiple Lagrangian non-intersections, Welshinger who explained his ap-proach to estimating Betti numbers of algebraic vari-

eties, and Eliashberg who explained recent advancesin symplectic flexibility;

• Mirror symmetry, possibly the most “explosive”topic relating symplectic topology to mathematicalphysics, was discussed by Ganatra, Sheridan, Perutz,Lau and Nadler. In particular, Sheridan explained hisproof of the HMS conjecture in a number of cases;

• Advances in symplectic dynamics appeared in thepresentations of Entov, Khanevsky and Buhovsky;

• Hamiltonian dynamics applications were covered bytalks of Usher, Schlenk, Gürel;

• New perspectives on Lagrangian topology werereflected in talks of Biran, Woodward, Borman,Solomon, Ekholm;

• Legendrian topology topics were discussed in talksof Hutchings and Honda. In particular, Hutchings’talk on applications of his Embedded Contact Ho-mology described some of the most fruitful recentdevelopments in the study of Reeb dynamics;

• Foundational issues that come into focus today ap-peared in the presentations of McDuff, Fukaya, andFrauenfelder;

• Finally, the talks of Oancea, Tolman, and Liu touchedon other topics of high interest today, among themstring topology and enumerative invariants.

2. Three insightful lecture series: The talks mentionedabove were complemented by lecture series, partic-ularly accessible to graduate students and young re-searchers.• Hofer talked about potential applications of today’s

most refined symplectic techniques to celestial me-chanics. The origins of symplectic topology lie inproblems that emerged from celestial mechanics, inparticular the n-body problem. Hofer’s perspectivewas that time has come for the modern tools of sym-plectic topology to be applied again effectively tothe mechanics of the solar system and, in particular,space travel;

• Abouzaid discussed the delicate details of coher-ent orientations in relation to the interplay betweenstring topology and symplectic homology of cotan-gent bundles;

• Sandon explained the discrete metrics on contacto-morphism groups that she recently introduced aswell as related techniques and conjectures.

3. A high number of young brilliant researchers: Itbecame clear, in part as a result of this conference,that symplectic topology is at a very special momentin its development. Suddenly, a new generation is

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entering the field with great energy and brilliance.Sheridan, Borman, Ganatra, Abouzaid, Sandon, Perutz,Buhovsky, Khanevsky, Usher, Frauenfelder, Solomon,Oancea are all young and extremely promising re-searchers who spoke at this conference. Some of themhave already made an important mark on the field andmost of the others will do so in the not too distant fu-ture. A great contribution to the success of the meet-ing was also made by the other participants so that, asa whole, most of the top world researchers in the sub-ject participated in this event in one form or another.

WorkshopMajor and Neglected Diseases in AfricaMay 6–10, 2013, OttawaSponsored by the CRM and the Society of Mathemati-cal Biology

Organizers:Julien Arino (Manitoba), Jane Heffernan (York)Speakers:Cameron Browne (Ottawa), David Buckeridge(McGill), Abba Gumel (Manitoba), Jane Heffernan,Senelani Dorothy Hove-Musekwa (NUST Zimbabwe),Michael Li (Alberta), Connell McCluskey (Wilfrid Lau-rier), Elaine Nsoesie (Harvard), Kathleen O’Reilly (Im-perial Coll.), Nitika Pai (McGill), Gauthier Sallet (IN-RIA Nancy), Kevin Schwartzman (McGill), RobertSmith (Ottawa), Donald Sutherland (CSIH), Kate Zin-szer (McGill), Pascal Zongo (Antilles et Guyane)Number of participants: 30The workshop on Major and Neglected Diseases inAfrica was sponsored by the CRM as part of the Mathe-matics of Planet Earth (MPE) thematic year. The work-shop organizers, Jane Heffernan and Julien Arino, arealso members of the Centre for Disease Modelling, agroup based at York University. The rationale for theworkshop stemmed from the observation that there areserious public health implications of the fact that whileAfrica counts 54 countries and 15 percent of the worldpopulation, the combined GDP of African countriesrepresented in 2003 just over 3 percent of the world’sGDP. From a demographic perspective, Africa is char-acterized by an over representation of youth (40 per-cent of its population is under 15), and a life expectancythat is below 65 years (e.g., 31.6 years in Botswana),compared to 82.6 years in Japan. Several factors con-tribute to this low life expectancy (e.g., poverty, inad-equate health care systems), but the main reason is thecompounding of these factors with the effect of several

major infectious diseases and some less known onesthat are plaguing the continent.

Mathematical models are increasingly accepted in thepublic health domain as tools to fight infectious dis-eases. Modelling is helpful mostly because it allows forsimple hypothesis testing where most other tests areimpossible. Modelling is also a valuable tool that al-lows to pinpoint gaps in data collection. The workshopfocused on some major killers (HIV/AIDS, malaria,and tuberculosis) and also considered some diseasesthat are, for one reason or another, less in the spot-light: childhood diseases, other viral/bacterial/vectordiseases, poliomyelitis. The objectives of the workshopwere the following:• To combine the expertise of public health officials

and researchers in biology and mathematical sci-ences in the areas of infectious diseases relevant toAfrica;

• To encourage and seek participation of African col-leagues, to foster collaborations between Canadianand African researchers;

• To compare experiences in dealing with publichealth authorities, helping all participants develop abetter understanding of this difficult yet crucial as-pect;

• To train junior researchers, postdoctoral fellows andgraduate students.

Each day of this five- day workshop was devoted to aparticular disease or group of diseases, with a few pre-sentations on the disease(s) of interest followed by agroup discussion on the subject. There were a total of18 presentations. Monday had talks about Poliomyeli-tis (morning) and Schistosomiasis and other neglectedtropical diseases (afternoon). Each of the next threedays was devoted to one of the “Big Three” infectiousdiseases, i.e., the diseases associated with the highestmortality rates in Africa: HIV/AIDS was discussed onTuesday, Malaria on Wednesday, and Tuberculosis onThursday. Finally, on Friday morning, the focus shiftedto the problem of surveillance. Each day featured fourplenary talks and two discussion sessions. Each diseasetopic included a talk from the public health perspec-tive and a mathematical modelling talk. Each publichealth talk reviewed past and current issues relatedto the infectious disease epidemiology, with certainAfrican regions being highlighted. The mathematicalmodelling talks provided an overview of the currentmodelling literature centered on the infectious diseasein question, and introduced some new models having

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the potential to address current issues in epidemiol-ogy. In the discussion sessions, participants identifiedgaps in our knowledge and discussed the role of math-ematical modelling in the particular thematic areas. Agroup of researchers from the workshop have contin-ued discussions and are currently working on a studyof community-based care and self-testing in HIV af-fected communities.

There were 30 registered participants to the work-shop, hailing from several countries: 1) Canada (19);2) France (2); 3) French Guyana (1); 4) Ghana (3); 5)United Kindgom (1); 6) USA (2); 7) Zimbabwe (2). Thepresence of participants from African institutions aswell as members of the African diaspora working inNorth America and Europe helped the workshop “stayon focus,” since many of the attendees had first-handexperience of the diseases being discussed. The work-shop was attended by participants with public healthand mathematical backgrounds, and participants at di-verse career stages: from master’s students to seniorresearchers and public health officials.

WorkshopThe Topology of 3-Dimensional ManifoldsMay 6–17, 2013, CRM

Organizers:Michel Boileau (Paul Sabatier), Steven Boyer (UQAM),Marc Lackenby (Oxford), Alan Reid (UT Austin)Lecturers:Ian Agol (UC Berkeley). Tao Li (Boston Coll.), JuanSouto (UBC)Speakers:Ian Biringer (Boston Coll.), Jeffrey F. Brock (Brown),Ken Bromberg (Utah), Nathan M. Dunfield (UI Urbana-Champaign), Stefan Friedl (Köln), Paolo Ghiggini(CNRS & Nantes), Joshua Evan Greene (Boston Coll.),Jesse Johnson (Oklahoma State), Alexander Kolpakov(Vanderbilt), Christopher J. Leininger (UI Urbana-Champaign), Yi Liu (Caltech), Darren Long (UCSanta Barbara), Jessica Purcell (Brigham Young), SaulSchleimer (Warwick), Genevieve Walsh (Tufts), DanielT. Wise (McGill), Zhongtao Wu (Caltech)Number of participants: 82The events surrounding the workshop “The topol-ogy of 3-dimensional manifolds” were held over twoweeks, from May 6 to May 17, 2013. The first weekwas devoted to students and other young mathemati-cians. Three mini-courses were given by Ian Agol, TaoLi, and Juan Souto, respectively, and David Gabai de-

livered the first two of his four Aisenstadt Chair lec-tures. The second week saw the completion of Gabai’slectures as well as a workshop focusing on recent ad-vances and future research directions in the topologyof 3-dimensional manifolds. Over eighty participantsfrom North America, Europe and Asia were attractedto the events.

Week 1 began with Juan Souto’s mini-course “Eigen-values of the Laplacian and the topology of hyper-bolic 3-manifolds,” which detailed how soft geomet-ric methods could be used to estimate such eigenval-ues. The theory was illustrated with examples from3-dimensional geometry leading to a proof that if Mis a closed hyperbolic 3-manifold, then the first non-zero eigenvalue of its Laplacian is bounded from aboveby the ratio of a constant depending on the Heegaardgenus of M and its volume. The second mini-course,presented by Ian Agol, focused on the fundamentalgroups of 3-manifolds, a field which has seen major ad-vances over the last decade. The first two lectures dealtwith consequences of Perelman’s geometrization the-orem and the tameness theorem of Agol and Calegari-Gabai. The last two lectures outlined the deep workof Dani Wise on special cube complexes as well asAgol’s contributions in this area leading to his recentproofs of the virtual Haken conjecture, Thurston’s vir-tual fibring conjecture, and the subgroup separabilityof Kleinian groups. Tao Li’s mini-course dealt withthe modern theory of Heegaard splittings. After dis-cussing basic examples and properties, strongly irre-ducible Heegaard splittings were introduced, leadingto a proof of the generalized Waldhausen conjecturethrough the use of essential laminations. Other topicsdiscussed were applications of the curve complex toHeegaard splittings and an outline of a constructionof a 3-manifold whose fundamental group has rankstrictly smaller than its Heegaard genus. Each mini-course ended with a list of open problems and futuredirections.

David Gabai gave two of his four Aisenstadt Chair lec-tures at the end of week 1, both of an expository na-ture. The subject of the first was Poincaré’s contribu-tions to topology, remarkable for their foundationaland seminal nature as well as their impact on subse-quent research. The second lecture surveyed the beau-tiful and mysterious field of the volumes of hyperbolic3-manifolds and discussed Gabai’s ongoing work withMeyerhoff and (Nathaniel) Thurston in the area. Hislast two Aisenstadt Chair lectures were incorporated

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into the workshop held during week 2. They focusedon the topology of the ending lamination space associ-ated with a hyperbolic surface. These spaces, importantin both hyperbolic geometry and geometric group the-ory, are the focus of much current research with manybasic questions remaining open. Gabai outlined his re-cent progress towards characterizing their topology.

Fifteen one-hour-long talks of exceptional quality rep-resenting the state of the art in a number of areasof low-dimensional topology were presented in theworkshop. Dani Wise opened the proceedings witha talk that outlined his proof with (Piotr) Przytyckithat the fundamental groups of mixed 3-manifolds arevirtually special. Groups were also the focus of talksby Stefan Friedl, Chris Leininger, and Ken Bromberg.Friedl surveyed his recent work with Silver andWilliams on HNN splittings of knot groups. Leiningerdescribed his results with Dowdall and Kapovich ontopological, geometric, and dynamical relations be-tween monodromies of splittings of certain free-by-cyclic groups. Bromberg reported on joint work withBestvina and Fujiwara determining necessary and suf-ficient conditions for the stable commutator length ofan element in the mapping class group to be positive.Zhongtao Wu talked about the rational genus of knotin a 3-manifold, a topological quantity related to stablecommutator length. In particular he discussed inequal-ities he determined with Ni using Heegaard-Floer ho-mology, which imply, for instance, that simple knotsin lens spaces are genus-minimizing in their homologyclass.

Saul Schleimer gave a new proof (joint with Wick-ens), based on the train-track machine, of Klarreich’stheorem: the Gromov boundary of the curve complexis homeomorphic to the space of ending laminations.He explained how their proof generalizes to cover theGromov boundary of the arc complex as well. Curvecomplexes were also central in Jesse Johnson’s talk.He described how the notion of distance for a Hee-gaard splitting, and a slight generalization known assubsurface projection distance, can be used to con-struct a manifold with multiple distinct low-distanceHeegaard splittings of the same (small) genus, and amanifold with both a high-distance, low-genus Hee-gaard splitting and a distinct, irreducible high-genus,low-distance Heegaard splitting.

The topology of geometric manifolds arose in severalcontexts. Jeff Brock described joint work with Min-sky, Namazi, and Souto concerning a general frame-

work for producing models for hyperbolic 3-manifoldswith bounded combinatorial descriptions. He appliedit to describe, for instance, a specific construction ofhomology 3-spheres Benjamini–Schramm convergingto hyperbolic 3-space. The latter was a key compo-nent in the talk of Nathan Dunfield, who discussed hiswork with Brock on relations between growth in ho-mology, L2 homology, and injectivity radius in tow-ers of hyperbolic 3-manifolds. Jessica Purcell outlinedher studies on the following question: If a geometri-cally finite hyperbolic compression body has a singleunknotting tunnel, is the tunnel isotopic to a geodesic?She conjectures the answer is yes. Genevieve Walsh’stalk focused on her work with Hoffman on Thurston’sDehn-surgery graph of 3-manifolds. Along the wayshe explained their construction of the first examplesof hyperbolic 3-manifolds with weight 1 fundamentalgroups that are not obtained via surgery on a knot inthe 3-sphere.

In adjacent dimensions, Ian Biringer described the ge-ometric limits of sequences of hyperbolic metrics onsurfaces determined by iterations of certain homeo-morphisms of the surface, giving a compressible ver-sion of examples due to Kerckhoff–Thurston, Mc-Mullen, and Brock. One highlight of the workshop wasAlexander Kolpakov’s description of his recent studywith Martelli of the cusps of finite-volume hyper-bolic 4-manifolds. In particular, they resolved a long-standing open problem by constructing the first exam-ples of one-cusped such manifolds.

Analytic invariants of 3-manifolds have had a pro-found impact on 3-manifold topology through Ricciflow, Heegaard Floer homology, and contact topologyover the last decade. Paolo Ghiggini described his foun-dational work with Colin and Honda on the isomor-phism between Heegaard Floer homology and embed-ded contact homology. Josh Greene gave a talk of greatclarity on his theorem that two reduced, alternating di-agrams for a pair of links are mutants if and only ifthe Heegaard Floer homology of the link’s brancheddouble-covers are isomorphic.

WorkshopImpact of Climate Change on BiologicalInvasions and Population DistributionsMay 12–17, 2013, BIRSSponsored by NSERC, the NSF, CONACYT, and theMinistry of Enterprise and Advanced Education of Al-berta

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Organizers:Henri Berestycki (ÉHÉSS), Alan Hastings (UC Davis),Mark Lewis (Alberta), Péter Molnár (Princeton)Speakers:Henri Berestycki, Michael Bonsall (Oxford), ChristinaCobbold (Glasgow), Chris Cosner (Miami), Kim Cud-dington (Waterloo), Laurent Desvillettes (ÉNS Ca-chan), Odo Diekmann (Utrecht), Claire Dooley (Ox-ford), William Fagan (Maryland), Jimmy Garnier(INRA Avignon), François Hamel (Aix-Marseille; IUF),Alan Hastings, Amy Hurford (Memorial), Alex Kise-lev (Wisconsin–Madison), Yuan Lou (Ohio State), MarkLewis, Brett Melbourne (CU-Boulder), Ehud Meron(Ben Gurion), Péter Molnár (Princeton), Paul Moor-croft (Harvard), Lionel Roques (INRA Avignon), LucaRossi (Padova), Rebecca Tyson (UBC Okanagan), MaryLou Zeeman (Bowdoin Coll.), Ying Zhou (Washing-ton), Huaiping Zhu (York)Number of participants: 39

Summer SchoolMathematics of Infectious DiseaseMay 19–27, 2013, YorkSponsored by the Fields Institute for Research in Math-ematical Sciences and Mitacs

Organizers:Jane Heffernan (York), Neal Madras (York), SeyedMoghadas (York), Jianhong Wu (York), Huaiping Zhu(York)Public Lecture Speakers:Carlos Castillo-Chavez (Arizona State), Mirjam Kret-zschmar (Utrecht), Eduardo Massad (São Paulo)Course Instructors:Linda J. S. Allen (Texas Tech), Julien Arino (Manitoba),Fred Brauer (UBC), Odo Diekmann (Utrecht), DavidFisman (Toronto), Jane Heffernan, Ying-Hen Hsieh(China Medical), Neal Madras, Seyed M. Moghadas,Beate Sander (PHO), Pauline van den Driessche (Vic-toria), James Watmough (New Brunswick), Ping Yan(PHAC), Huaiping Zhu

WorkshopExtremal Kähler MetricsMay 27–June 1st, 2013, CRM

Organizers:Vestislav Apostolov (UQAM), Claudio Arezzo (ICTP),Xiuxiong Chen (Stony Brook), Claude LeBrun (StonyBrook)

Speakers:Olivier Biquard (ÉNS), Xiuxiong Chen, Renjie Feng(McGill), Akito Futaki (Tokyo), Weiyong He (Ore-gon), Hongnian Huang (École Polytechnique), Chi Li(Princeton), Toshiki Mabuchi (Osaka), Sean T. Paul(Wisconsin–Madison), Yann Rollin (Nantes), Yuji Sano(Kumamoto), Cristiano Spotti (IHÉS), Ioana Suvaina(Vanderbilt), Christina W. Tønnesen-Friedman (UnionColl.), Hajime Tsuji (Sophia), Craig van Coevering(USTC), Jeff Viaclovsky (Wisconsin–Madison), BenWeinkove (Northwestern)Number of participants: 43This one-week workshop, held at the Centre derecherches mathématiques, was focused on the studyof the Calabi problem in Kähler Geometry. The work-shop was attended by over 40 participants, rangingfrom algebraic geometers to differential geometers toanalysts. Most participants were speakers and most at-tended every talk. Many new results were reported forthe first time during the workshop and many partici-pants left Montreal ready to work on new projects.

We highlight the two lectures series, one given by X.Chen and S. Sun (a total of three lectures) at the be-ginning of the workshop and the three Aisenstadt lec-tures given by G. Tian at the end of the workshop,in which the recent breakthrough in the Yau-Tian-Donaldson conjecture in the Fano case was presented.Other facets of the theory include the study of mod-uli of extremal Kähler metrics and desingularisations(talks by O. Biquard, J. Stoppa, I. Suvaina), SasakianGeometry (talks by W. He, C. Tønnesen-Friedman,C. van Coevering), evolution equations in Kähler ge-ometry (talks by A. Futaki, H. Huang, B. Weinkove),study of algebro-geometric notions of stability (C. Li,T. Mabuchi, Y. Rollin, S. Paul, Y. Sano), and probabilis-tic methods (R. Feng).

Thus, in an intensive week, the program succeeded intying together most of the new results in the subjectand a variety of new projects were born. The partici-pants affirmed frequently and spontaneously that theprogram was a great success.

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Summer SchoolThe Mathematics Behind BiologicalInvasionsMay 19–27, 2013, YorkSponsored by PIMS, the International Graduate Train-ing Centre (IGTC) in Mathematical Biology, the Centrefor Mathematical Biology, the University of Alberta,and Mathematics of Planet Earth 2013

Organizers:Thomas Hillen (Alberta), Mark Lewis (Alberta)Speakers:Alan Hastings (UC Davis), Mark Lewis, Jonathan Sher-ratt (Heriot-Watt), Sergei Petrovskii (Leicester)

WorkshopModuli Spaces and Their Invariants inMathematical PhysicsJune 3–14, 2013, CRM

Organizers:Jacques Hurtubise (McGill), Lisa Jeffrey (Toronto), Jo-hannes Walcher (McGill)Speakers:Murad Alim (Harvard), Paul S. Aspinwall (Duke), TomBaird (Memorial), Philip Boalch (ÉNS; CNRS), VincentBouchard (Alberta), Andrei Căldăraru (Wisconsin–Madison), Benoit Charbonneau (St. Jerome), SergeyCherkis (Arizona), Andrew Dancer (Oxford), KeshavDas Gupta (McGill), Tudor Dan Dimofte (IAS), RonDonagi (Pennsylvania), Charles Doran (Alberta), BrentDoran (ETH Zürich), Bertrand Eynard (CEA/Saclay),Jonathan Fisher (Toronto), Davide Gaiotto (Perime-ter Inst.), Peng Gao (Stony Brook), Marco Gualtieri(Toronto), Babak Haghighat (Harvard), John Har-nad (Concordia), Tamas Hausel (EPFL), Spiro Ka-rigiannis (Waterloo), Matt Kerr (WUSTL), BorisKhesin (Toronto), Can Kozcaz (SISSA), Joshua Lapan(McGill), Chiu-Chu Liu (Columbia), Alexander Mal-oney (McGill), Eckhard Meinrenken (Toronto), Ruxan-dra Moraru (Waterloo), Hiraku Nakajima (Kyoto),Tony Pantev (Pennsylvania), Brent Pym (Toronto),Steven Rayan (Toronto), Mauricio Romo (Kavli Inst.),Jihye Seo (McGill), Vivek Shende (UC Berkeley), JörgTeschner (Hamburg), Valerio Toledano Laredo (North-eastern), Misha Verbitski (Glasgow), Michael LennoxWong (EPFL), Kota Yoshioka (Kobe), Matthew B.Young (Stony Brook)Number of participants: 71

Moduli spaces appear in a variety of contexts in bothmathematics and physics. In physics, they are often, insome sense, the natural spaces for functional integra-tion, after one has quotiented out infinite dimensionalspaces of symmetries; in mathematics, they exhibit abewildering array of structure, whose discovery is of-ten due to intuition from physics. The two-week-longextended workshop, Moduli Spaces and their Invari-ants in Mathematical Physics, held June 2 to 14th, 2013,was a true meeting of cultures, with all the fruitful in-teraction (and occasional frustration) that this implies.It provided an opportunity to see the wide variety ofthemes that interplay in the area. Within the limits ofthe availabilities of the different speakers, the confer-ence organised itself around some of these themes, al-ternating in a rough fashion between more mathemat-ical topics and more physical ones. These include:• Metrics with special holonomy. On these, we saw

deep and interesting results on hyperkähler mani-folds presented by Andrew Dancer, Sergey Cherkis,on G2 structures by Spiro Karagiannis, and on hyper-complex structures by Misha Verbitsky. TamasHausel gave some very interesting computationalevidence on the Betti numbers of hyperkähler man-ifolds.

• Calabi–Yau manifolds, their moduli, and their in-variants. The geography of the Calabi–Yau mod-uli was explored in various aspects by both PaulAspinwall and Charles Doran. Around the gen-eral theme of toric Calabi–Yau and the Bouchard–Klemm–Marino–Pasquetti conjecture on their rela-tion to the Eynard–Orantin invariants, Bertrand Ey-nard gave his explanation and proof for smooth vari-eties, and both Melissa Liu and Vincent Bouchard ex-plained the extension to orbifolds. John Harnad gavea survey of various appearances of the tau functionin the computation of numerical invariants. In a re-lated theme, Tony Pantev talked about the complexmoduli of Landau–Ginsburg models.

• Symplectic geometry and integrable systems. In somesense, this is a more classical part of the story,but with some beautiful surprises: Jonathan Fishergave a talk on analogues of polygon spaces, andBoris Khesin explained his generalizations of penta-gram maps. Vivek Schende told us about Legendrianknots, and Eckhard Meinrenken explained how weshould understand the Verlinde formulae for non-simply connected groups.

• Non-Kähler geometry. In this emergent area, Ruxan-dra Moraru explained some gauge-theoretical work

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on balanced HKT manifolds, and Andrei Căldăraruspoke on moduli of sheaves on non-Kähler mani-folds.

• Wild character varieties and Stokes phenomena. Whilethis is in some ways the most classical area of all theconference, a clear understanding of the Stokes phe-nomenon is only just emerging. Marco Gualtieri andBrent Pym explained their new groupoid approachto wild character varieties, Michael Wong gave atalk on the arithmetic aspects of these varieties, andPhilip Boalch’s wide-ranging survey explained somerather subtle isomorphisms that take place.

• Gauge theory. The conference opened with a beau-tiful talk by Hiraku Nakajima, explaining some ofthe support for the Alday-Gaiotto-Tachikawa (AGT)conjecture on the cohomology ring of instantonmoduli spaces; Kota Yoshioka explained some resultson Bridgeland stability and stable sheaves on abeliansurfaces; Benoit Charbonneau talked about variousaspects of the Nahm transform for spatially periodicinstantons, Tom Baird on the real aspects of mod-uli of vector bundles over a curve, and Steven Rayantalked on the moduli of twisted Higgs bundles.

• Moduli of curves. This other central topic was wellrepresented by the talks of Ron Donagi, who ex-plained his rather surprising result with Witten onthe structure of supermoduli space, of Brent Doran,who talked about moduli of stable rational curves,and Jihye Seo explaining some of the physical as-pects of the degeneration of hyper-elliptic curves.

• Algebraic aspects of moduli. There are quite rich al-gebraic structures underlying all of these modulispaces, and some of these appeared in the talks byValerio Toledano Laredo (“From Yangians to quan-tum loop algebras via abelian difference equations”)and Matthew B. Young (Hall modules of quivers).

• Computation of Gromov-Witten Invariants. One ex-citing recent development in invariants of modulispaces is supersymmetric localization, amongst oth-ers as a tool for computation of Gromov-Witten in-variants, without mirror symmetry; Joshua Lapanreviewed the closed string story and Mauricio Romoexplained the generalization to open strings.

• Quantization and topological strings. Quantization ofmoduli spaces and the associated integrable systemsis a notoriously difficult topic of recurring interest.Jörg Teschner explained the quantization of mod-uli of curves as suggested by the AGT relation togauge theory. Moving to higher dimensions, MuradAlim revisited the structure of Bershadsky-Cecotti-

Ooguri-Vafa rings on moduli of Calabi-Yau three-folds that are analogous to quasi-modular forms.Matt Kerr discussed the invariants of algebraic cy-cles that play a fundamental role at the semi-classicallevel.

• M-theory: Supersymmetric localization and the AGTcorrespondence are but two topics showcasing theimpressive progress in the physical calculation of in-variants of moduli spaces in various corners of M-theory. Babak Haghighat presented his recent workon a variant correspondence, with different amountsof supersymmetry and firmly rooted in M-theory.Can Kozcaz calculated the elliptic genus of M2-branes suspended between M5-branes.

• Applications: We invited several talks on applica-tions of moduli spaces for concrete physical ques-tions in string theory. From the side of the heteroticstring, Peng Gao discussed questions of stability invarious classes of bundle constructions on Calabi-Yau threefolds. Keshav Dasgupta took first steps inthe exploration of gauge/gravity duality in that het-erotic theory. Alex Maloney exposed the relation be-tween 3D quantum gravity and a number of chal-lenging problems in moduli of Riemann surfaces.

The conference opened on a mathematical theme, withthe talk by Hiraku Nakajima; on the other hand, bothweeks closed on a strongly physical note, with AlexMaloney in the first week, and Keshav DasGupta in thesecond. The conference moved for one day out to MontSaint Hilaire, with talks in the morning and an explo-ration of the Nature Reserve in the afternoon, with ofcourse more discussion taking place under the stimu-lation of exercise; the weather gods smiled on us withone of the few sunny days in an otherwise rather rainytwo weeks. One nice aspect of the conference was astrong participation by post-doctoral fellows, whosepresence was greatly helped by funding from the NSF,to whom we are grateful.

WorkshopLow-Dimensional Topology after FloerJuly 8–12, 2013, CRM

Organizers:Hans Boden (McMaster), Olivier Collin (UQAM)Speakers:Kenneth Baker (Miami), John Baldwin (Boston Coll.),Vincent Colin (Nantes), Christopher Cornwell (Duke),John Etnyre (Georgia Tech), Kim A. Froyshov (Aarhus),Paolo Ghiggini (CNRS; Nantes), Elisenda Grigsby

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(Boston Coll.), Matthew Hedden (Michigan State),Ko Honda (Southern California), Michael Hutchings(UC Berkeley), Paul Kirk (IU Bloomington), CiprianManolescu (UC Los Angeles), Lenhard L. Ng (Duke), Ja-cob Rasmussen (Cambridge), Nikolai Saveliev (Miami),Clifford Taubes (Harvard), Stefano Vidussi (UC River-side)Number of participants: 76The conference focused on the current impact of Floerhomology methods in low-dimensional topology. Inrecent years, the interactions between geometric, con-

tact, and symplectic topology and the many types ofFloer homologies have proved very successful for solv-ing outstanding questions in low-dimensional topol-ogy, and there are signs that more breakthroughs willoccur in the near future. This event brought togetherleading experts working in these related areas, but alsoa special emphasis was put on the invitation of up-and-coming researchers and graduate students, someof whom also attended the SMS summer school onthe mathematics and physics of knot homologies (sum-marized in the CRM annual report for the year 2013–2014).

Past Thematic Programs

The Centre de recherches mathématiques has organized thematic activities every year since 1993. From 1987to 1992, the CRM organized various types of activities, including special semesters, concentration periods, andthematic activities. Here is a list of the main activities organized by the CRM since 1987.

January–July 2012 Geometric Analysis andSpectral TheoryJune–December 2011 Quantum InformationJanuary–June 2011 StatisticsJuly–December 2010 Geometric, Combinatorialand Computational Group TheoryJanuary–April 2010 Number Theory asExperimental and Applied ScienceAugust–December 2009 Mathematical Problems inImaging Science2008–2009 Joint CRM–PIMS Program: Challengesand Perspectives in Probability2008–2009 Probabilistic Methods in MathematicalPhysics

January–June 2008 Dynamical Systems andEvolution EquationsJune–December 2007 Applied Dynamical SystemsJanuary–June 2007 Recent Advances inCombinatoricsJune–December 2006 Combinatorial Optimization2005–2006 Analysis in Number Theory2004–2005 The Mathematics of Stochastic andMultiscale Modelling

2003–2004 Geometric and Spectral Analysis2002–2003 Mathematics in Computer Science2001–2002 Groups and Geometry2000–2001 Mathematical Methods in Biology andMedicine1999–2000 Mathematical Physics1998–1999 Number Theory and ArithmeticGeometry

1997–1998 Statistics1996–1997 Combinatorics and Group Theory1995–1996 Applied and Numerical Analysis1994–1995 Geometry and Topology1993–1994 Dynamical Systems and Applications1992 Probability and Stochastic Control(special semester)

1991–1992 Automorphic Forms in Number Theory1991 Operator Algebras (special semester)1990 Nonlinear PDEs and Applications(concentration period)1988 Shimura Varieties (special semester)1987 Quantum Field Theory (special semester)1987–1988 Fractals: Theory and Application1987 Structural Rigidity (special semester)

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The CRM’s general program funds a wide variety of scientific events, both on the premises of the CRM andelsewhere in Canada. Whether it be for specialized workshops attended by a small number of researchers or

large meetings attended by hundreds of participants, the general program promotes research in the mathematicalsciences at all levels. The program is quite flexible, allowing projects to be considered as they arise. The reports arepresented in the language in which they were submitted.

CRM activities

The 23rd International Meeting onProbabilistic, Combinatorial andAsymptotic Methods for the Analysis ofAlgorithms (AofA 2012)June 18–22, 2012, CRMSponsored by the CRM, INRIA, and NSERC

Organizers:Nicolas Broutin (INRIA Rocquencourt), Luc Devroye(McGill)Plenary Lecturers:Amin Coja-Oghlan (Warwick), Michael Drmota (TUWien), Svante Janson (Uppsala), Claire Mathieu(Brown, CNRS, and ÉNS), Avi Wigderson (IAS)Number of participants: 72The conference consisted of 5 invited talks by dis-tinguished researchers in the field of algorithms andcombinatorial structures: Amin Coja-Oghlan, MichaelDrmota, Svante Janson, Claire Mathieu, and AviWigderson; and 32 presentations that had been se-lected by the program committee after submission ofa 12-page abstract.

The meeting is part of a series of conferences andworkshops that has been going on for more than twodecades. It aims at providing a venue for the peopleworking in the field of theoretical computer science ordiscrete mathematics in order to present the recent ad-vances, exchange ideas, and foster new contacts andcollaborations about the asymptotic behaviour of ran-dom combinatorial structures and their applications tothe analysis of algorithms and data structures. The par-ticipants have mixed backgrounds going from combi-natorics and complex and asymptotic analysis to prob-ability theory and stochastic processes.

It is remarkable that the meeting at the CRM showedincreasing signs that the community is blending: inparticular, the different groups on which the meet-ing traditionally relies (analysts, combinatorists, prob-abilists) are now certainly more porous than they usedto be. We were glad to see that the proportion of stu-dents and young researchers had not declined, in spite

of the distance to Europe where most of the commu-nity lies.

This year’s meeting was especially successful withtalks covering a broad range of topics in algorithmsor data structures, combinatorics, discrete probability,or methodology. All the talks were very lively andprovided interesting and new points of view on im-portant questions or novel applications. A number ofopen problems were raised, in particular by the invitedspeakers, some of which are traditionally chosen inneighbouring fields in order to provide the participantswith an alternative point of view on the important cur-rent directions of research in algorithms and randomstructures.

On the topics of algorithms, two of the invited speak-ers delivered wonderful lectures on approximation al-gorithms (C. Mathieu) and learning (A. Widgerson)which raised many questions and open problems.J. Gaither presented new results on the number of pro-tected nodes in random tries and suffix trees, whichhave implications on the performance of algorithmsmanipulating strings. Probabilistic counting and its ap-plications were addressed in the talks by M. Fuchs andC. Martinez. O. Roussel presented extensions to shuf-fle products of the widely used Boltzmann samplers.D. Shymura discussed geometric algorithms for shapematching of surprising simplicity that rely on randomsampling. C. Fricker demonstrated that the methodscan be applied to other concrete problems such as bikesharing systems (BIXI, Vélib’). The other talks on algo-rithms included B. Vallée’s demonstration that Euclid’salgorithm is totally Gaussian, J. Fill’s recent work onthe performance of Quicksort measured in number ofsymbol comparisons, Z. Golebiewski’s new analysis ofleader election based on the trie data structure, E. Gas-siat’s work on lossless compression via adaptive cod-ing for countable alphabets, and I. Eisner’s applicationof domination analysis to scheduling problems.

Discrete probability was addressed in S. Janson’s in-vited lecture on branching processes. Random trees

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and their properties were also the main topic of thetalks by S. Wagner on additive functionals with smalltoll functions, and V. Kraus on transversals in randomtrees, which is very surprisingly inspired from applica-tions to antiterrorism. S. Miracle discussed the mixingtime of Markov chains on planar triangulations. Urnmodels and their asymptotic behaviour were the topicof the talks of B. Mocrette (random balanced urns)and M. Kuba (diminishing urns via death processes).G. Fayolle presented his results with K. Raschel on thenumber of random walks constrained to live in thequarter plane, which has generated much interestingresearch since the proof that the generating functionfor Gessel’s walk is algebraic. Y. Ponty discussed theword collector, a model inspired by the sampling ofprotein configurations. L. Lhote discussed hidden pat-terns in strings under general models of sources.

More combinatorial themes were also addressed inM. Drmota’s invited lecture on universal results onsubcritical random graphs, and A. Coja-Oghlan’s in-troduction to the currently hot topic of phase tran-sitions in random structures and their connection tohardness of optimization problems. Some interest-ing new aspects of essential combinatorial structureswere presented by D. Ralaivaosaona (integer parti-tions), V. Feray (random partitions), Z. Gao (randomcompositions), and P. Jacquet (joint string complex-ity). The talks on combinatorics also included discus-sions of less mainstream problems such as random sub-groups of a free group (F. Bassino), random polyomi-nos in relation to Stokes phenomenon in complex anal-ysis (L. Hickok), and min-weight digital expansions(C. Heuberger).

Moreover, new methodological advances were pre-sented by W. Spzankowski on the asymptotic of solu-tions of binomial recurrences, J. Cichon on Bernoullisums, and J. Kieffer on divide-and-conquer recur-rences. Furthermore, B. Gittenberger discussed hisvery recent and far reaching results on Gaussian limitdistributions for the solutions of infinite systems ofequations. These advances will certainly be central to anumber of applications in combinatorics in the future.

Finally, the authors of abstracts published in the con-ference have been offered the opportunity to submitlong versions of their work to a special issue of thejournal “Combinatorics, Probability and Computing,”which will be dedicated to the memory of Philippe Fla-jolet in connection with AofA 2012. This special issueedited by N. Broutin (INRIA), J. Fill (Johns Hopkins),

Markus Nebel (Kaiserslautern), and M. D. Ward (Pur-due) will gather the best contributions and confirm thesuccess of the conference held at the CRM.

WorkshopN = 2 Jeometry and ApplicationZJune 20–22, 2012, McGillSponsored by the Mathematical Physics Laboratory

Organizers:Keshav Dasgupta (McGill), Jihye Seo (McGill), Jo-hannes Wacher (McGill)Speakers:Philip Argyres (Cincinnati), Chris Beem (Simons Ctr.),Clay Cordova (Harvard), Jacques Distler (UT Austin),Amihay Hanany (Imperial Coll.), Ken Intriligator(UC San Diego), Peter Koroteev (Minnesota), DanielKrefl (UC Berkeley), David Kutasov (Chicago), SatoshiNawata (Perimeter Inst.), Chan Youn Park (Caltech),Ramadevi Pichai (IIT Bombay), Shlomo Razamat (IAS),Nathan Seiberg (IAS), Sav Sethi (Chicago)Number of participants: 19Supersymmetric theories with 8 supercharges (this be-ing N = 2 times the minimal amount required for4-dimensional Lorentz invariance) are models of rel-ativistic quantum physics that both have nontrivialperturbative and nonperturbative dynamics, and areamenable to exact analysis. Ever since the celebratedsolution of N = 2 supersymmetric gauge theory bySeiberg and Witten, the investigation of the rich un-derlying geometric structure together with its embed-ding into string theory has proven remarkably fruitful.These developments first of all triggered the discoveryof dualities in string theory itself. Secondly, they re-sulted in an impressive amount of results of relevanceto pure mathematics. Thirdly, they have been the start-ing point for many of the more convincing recent at-tempts to reconstruct particle physics from a funda-mental theory, by breaking N = 2 to N = 1 su-persymmetry with branes and fluxes. The last threeyears have witnessed an impressive revival of interestin N = 2 theories. Among recent results that moti-vated this workshop, we mention the presentation of anew class of superconformal theories by Gaiotto, theircorrespondence with certain 2-dimensional (bosonic)conformal theories of Liouville type, as well as the“Nekrasov–Shatashvili” relation between Ω-deformedN = 2 theories and quantum integrable systems, andthe embedding of all of the above within string theory.

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The scope of the workshop (as hinted by the title) wassomewhat larger and included also supersymmetricfield theories in other dimensions, and with differentamounts of supersymmetry. This framework broughttogether a number of established researchers, includ-ing several of the pioneers, and representatives of thenew generation who entered the field in recent years.The goal was to provide a forum for discussion of re-cent results in the light of original methods and ideas.

The workshop was hosted by the McGill physics de-partment, and the format was modelled after severalother successful events organized by McGill’s Centrefor High Energy Physics about three to four timesa year: two and a half days with around 15 exter-nal speakers in a relaxed atmosphere with ample timefor discussions. Such a format represents a particularbenefit for graduate students around Montréal, whohave the opportunity to meet and interact with dis-tinguished scholars in their chosen field of study. Asconfirmed by many of the participants, the organizerssucceeded in striking the right balance this time again.Progress in this branch of mathematical physics is ex-pected to continue at the same amazing pace, and ev-eryone left Montréal looking forward to a future meet-ing.

Summer SchoolSéminaire de Mathématiques Supérieures2012Probabilistic CombinatoricsJune 25–July 6, 2012, CRMSponsored by the Fields Institute for Research in Math-ematical Sciences, PIMS, the CMS, the Université deMontréal, the MSRI, and the CRM

Organizers:Louigi Addario-Berry (McGill), Luc Devroye (McGill),Bruce A. Reed (McGill)Speakers:Nikhil Bansal (TU Eindhoven), Hamed Hatami(McGill), Penny Haxell (Waterloo), James R. Lee(Washington), Colin McDiarmid (Oxford), Yuval Peres(Microsoft Res.), Alex Scott (Oxford), Perla Sousi (Cam-bridge), Prasad Tetali (Georgia Tech), Eric Vigoda(Georgia Tech), Peter Winkler (Dartmouth Coll.)Number of participants: 81The 2012 Séminaire de Mathématiques Supérieures in-troduced nearly eighty young researchers from east-ern and western Canada, the USA, Australia, Belgium,Brazil, the Czech Republic, England, France, Germany,

Hungary, India, the Netherlands, and Sweden, to someof the most exciting subjects of active research in thearea of probabilistic combinatorics. The subjects ad-dressed at the summer school can be roughly arrangedinto two overlapping themes:(1) properties of discrete Markov chains; and(2) new techniques for understanding structural prop-

erties of deterministic and random graphs.The majority of the eleven invited speakers stayed forat least one full week of the SMS, and four of thespeakers (Hatami, McDiarmid, Scott, Winkler) stayedfor both weeks. This gave the students plenty of oppor-tunity to interact with the speakers outside of the lec-ture hall, which contributed substantially to the scien-tific quality of the meeting. (For example, one speaker,Prasad Tetali, ended up giving a supplementary “mini-course” to a subset of the students who were inter-ested in hearing more detail about some of the researchTetali touched on in his lectures.)

THEME 1: DISCRETE MARKOV CHAINS

The flagship lectures on this theme were by Peter Win-kler, who gave a sequence of five ninety-minute talkson random walks on graphs. This (by now) classi-cal subject has lots of beautiful theorems and scoresof applications in mathematics and computer science.Nonetheless, new and remarkable results keep com-ing in. Winkler started by reviewing the classical re-sults in the area, including the connection betweenrandom walks and electrical networks and its exten-sions. He then moved to some exciting new research,including recent results and open problems on cover-ing the vertices and edges of a graph, the use of po-tential functions to prove universal bounds for covertimes, and cat-and-mouse (or cop-and-robber) gameson graphs. James Lee’s talks dovetailed beautifullywith Winkler’s, while consisting of more classicallyprobabilistic content. Lee presented his recent tour deforce with Ding and Peres, relating the cover time ofreversible Markov chains to the extremes of an asso-ciated Gaussian process. This research has now ap-peared in the Annals of Mathematics. Lee provided abrief background on Gaussian processes and beauti-fully presented Talagrand’s majoring measures theo-rem. He then explained how he, Ding, and Peres usedthe majorizing measures theory to exhibit a close con-nection between the cover time of a graph and the ex-pected square of its Gaussian free field.

The main tool allowing results for the Gaussian freefield to be transferred to the setting of Markov chains is

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the Dynkin isomorphism theory for Markov processes.While this connection is extremely useful and has al-ready resulted in solutions to some open questions oncover times, it is also rather mysterious even in ex-tremely simple examples. Lee discussed some naturalstarting points for possible research into the deeperstructure behind the Dynkin theory. Prasad Tetali’stalks, on geometric and functional analysis on graphs,were conceptually linked to those of James Lee viathe connection between isoperimetric inequalities andextremes of Gaussian processes. Tetali began with areview of some classical isoperimetric and functionalinequalities in discrete spaces, with applications toconcentration of measure and convergence to equilib-rium of finite Markov chains. He then presented recentresults on generalizations of Cheeger-type inequali-ties and refinements of Brunn-Minkowski inequalities,which suggest new directions for interesting researchin geometric and functional analysis on graphs. PerlaSousi presented her recent result, joint with YuvalPeres (and independently proved by Roberto Oliveira)on the equivalence of a broad family of notions of mix-ing time. Most notable among these is the fact that forreversible Markov chains, the mixing time is equiva-lent to the hitting time of large sets. This easily-statedfact provides a robust equivalent of the mixing timethat can be used both to simplify many existing proofsand to derive new results. Sousi highlighted one suchresult, related to a geometric characterization of themixing time for random walks on trees.

Yuval Peres’s lectures were on the subject of randomwalks on infinite graphs, which despite being moreclassical is still rife with open problems and areaswhere our understanding is incomplete. At the outset,Peres motivated his lectures with the following ques-tion: which of the following random walks on Z2 aretransient and which are recurrent?(1) In Z2, at times t ∈ [4k, 2·4k) we go up or down

with equal probability. At times t ∈ [2·4k, 4k+1),we go left or right with equal probability.

(2) In Z2 , if the current node has been visited before,then move left or right with equal probability; oth-erwise go up or down with equal probability.

(3) InZ2 , if |x| ≥ |y| then we go up or down each withprobability 0.3, and left or right each with proba-bility 0.2. This is reversed if |y| > |x|.

(4) In Z3, fix two mean-zero measures µ1, µ2 that aretruly 3D (that is, neither µ1 nor µ2 assigns proba-bility 1 to any hyperplane) with bounded support.

If Xt has been visited before, then Xt+1−Xt ∼ µ2

, else Xt+1−Xt ∼ µ11.(It turns out that 1, 3, and 4 are transient, and it is anopen problem to determine transience or recurrencefor number 2.) Peres then presented a wide range ofquestions and results on transience, recurrence, andspeed of random walks on various models of infi-nite graphs, with a particular focus on highlightingbasic gaps in our conceptual understanding and cur-rent techniques. Finally, Eric Vigoda’s talks formed abridge between the first and second themes, present-ing results related to Markov Chain Monte Carlo algo-rithms for generating random colourings of graphs ofbounded degree. Vigoda explained the basic couplingtechnique, and its refinement – known as path cou-pling – due to Bubley and Dyer. He then explainedthe well-known result of Mark Jerrum on rapid mixingof the Glauber dynamics for colouring when the num-ber of colours exceeds twice the maximum degree ∆.Vigoda followed this up with various improvements,beginning with his own famous result showing rapidmixing for the Glauber dynamics with 11∆/6 colours,via the analysis of a more complicated chain that flips2-colour components. He also showed how a multi-step coupling can be used to get improved results (as-suming lower bounds on the girth and on the maxi-mum degree, ∆). Finally, he explained a beautiful useof spectral graph theory to obtain improved results forplanar graphs or graphs embeddable on a fixed surface.

THEME 2: COLOURINGS, CLIQUES, AND CONNEC-TIVITY

Many questions in combinatorics concern the relation-ship between the local and global structure of a graphor set system. For instance, what can we say aboutthe subgraphs of a graph with large chromatic num-ber? What about graphs without large cliques or in-dependent sets? How uniformly is it possible to dis-tribute edges in a graph? In 7.5 hours of lectures, AlexScott presented a wide range of results and conjecturesof this flavour, touching on the Erdős-Hajnal Conjec-ture, the Gyárfás-Sumner Conjecture, discrepancy forgraphs and hypergraphs, and recently developed VC-dimension techniques. Nikhil Bansal gave another ex-tended mini-course of 7.5 hours, which brought theparticipants to the edge of existing knowledge in dis-crepancy theory. Discrepancy theory deals with thefollowing type of question. Given a set-system, finda red-blue colouring of the elements such that eachset is coloured as evenly as possible. Perhaps surpris-

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ingly, this notion has a wide variety of applicationsboth in computer science and mathematics, and sev-eral techniques (many of them non-constructive) havebeen developed to understand the discrepancy of vari-ous set-systems. Recently, there have been several newdevelopments in discrepancy based on connections tosemidefinite programming. This connection is usefulis various ways. It gives efficient polynomial-time al-gorithms for several problems for which only non-constructive results were previously known. It alsoleads to several new structural results, such as thetightness of the so-called determinant lower bound,and bounds on the discrepancy of unions of set-systems. Bansal presented these results in detail andtouched on several related concepts such as corre-lated Brownian motions, the non-constructive entropymethod, Gaussian rounding, and SDP duality.

Penny Haxell’s lectures had the intriguing title “atopology-free topological method.” Over the last dozenyears or so, certain topological methods have been de-veloped and used to prove a family of results relatedto the following general problem. Let G be a graphwhose vertex set is partitioned into nonempty setsV1, . . . , Vr . What conditions will guarantee thatG con-tains an independent set v1, . . . , vr such that vi ∈ Vi

for each i? This family of results includes theoremson matchings in hypergraphs, list colouring, strongcolouring, and Aharoni’s proof of Ryser’s longstandingconjecture on packing and covering in tripartite hy-pergraphs. The topological arguments used are basedon the notion of topological connectivity of simplicialcomplexes. Haxell has recently developed a method forestablishing this entire theory using only elementarycombinatorial arguments, and this approach was thesubject of her SMS lectures.

Colin McDiarmid presented some recent break-throughs on a classic question in probabilistic graphtheory: what is the typical behaviour of the chromaticnumber χ(G) of a graph G? If Rn denotes some sort ofrandom graph on n vertices, can we determine a func-tion f(n) such that χ(Rn)/f(n) → 1 in probability asn → ∞? If so, what is f(n)? Can we bound the typi-cal spread of the values χ(Rn)? Is χ(Rn) usually closeto ω(Rn), the maximum size of a complete subgraph?McDiarmid presented a variety of his recent results; hislectures focused primarily on the classical Erdős-Rényior Bernoulli random graph G(n, p) (both in the densecase where p is a constant and in the sparse case wherenp is constant), and on random geometric graphs. He

also touched on other graph invariants such as edge-chromatic number (chromatic index), list chromaticnumber, total chromatic number, achromatic number,improper chromatic number, and span. Perhaps mostnotably, he presented a recent technique that yieldsimproved estimates for χ(G(n, p)) in the dense case,and a surprising “phase change” that occurs whencolouring random geometric graphs.

The subject of influences is key to the understandingof phase transitions and sharp thresholds for variousproperties of discrete systems, including colouring ofgraphs, satisfiability of random formulas, and connec-tivity of random networks. Hatami presented the basicnotion of the influence of a variable on a Boolean func-tion, then sketched the proof of the Friedgut’s theoremstating that if f : 0, 1n → 0, 1 has small total in-fluence then it essentially depends on few coordinates.This theorem does not hold when the uniform distribu-tion on 0, 1n is replaced with the p-biased distribu-tion for a small value of p. He discussed the relevanceof this case to the study of the threshold phenomenon,and then sketched the proof of his own recent result,which characterizes the structure of Boolean functionswith small total influences on general product proba-bility spaces. The latter result has garnered substantialattention and has recently appeared in the Annals ofMathematics.

2nd Conference GNU Octave [free yournumbers]July 16–20, 2012, CRMSponsored by the CRM and the Université de Montréal

Organizer: Jordi Gutiérrez HermosoNumber of participants: 20GNU Octave is a free software that is quite similar toMatlab and thus includes algorithms for the numer-ical solution of linear and nonlinear problems. It al-lows one to perform other numerical experiments aswell and provides extensive graphics capabilities fordata visualization and manipulation. Octave is a high-level interpreted language but can also be used to writenon-interactive programs. OctConf2012, which tookplace at the CRM in July 2012, is part of a series ofworkshops geared towards people with an interest inOctave. The workshop was very successful. Over thecourse of five days, twenty participants were involved,and all but two were at the workshop for at least fourdays. The goal of the first two days was to provideinformation and the latest updates on development

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methodologies. The next three days consisted of opendiscussion and development. The schedule was fol-lowed with almost no modification. We refer the readerto http://jordi.inversethought.com/blog/octconf-2012-report/ for more details. The following talks tookplace:(1) What is Octave? (Jordi Gutiérrez Hermoso)(2) Octave’s architecture (Jordi Gutiérrez Hermoso)(3) Status of Octave (John W. Eaton)(4) Octave Speed and Cell Arrays (Daniel Sebald)(5) JIT Compiler (Max Brister)(6) The Octave GUI (Jacob Dawid)(7) Agora Octave and Packaging (Carlo de Falco,

David Pinto, and Juan Pablo Carbajal)(8) Bringing Least-Squares Spectral Analysis to Oc-

tave (Ben Lewis)(9) BIM package (Carlo de Falco)

Mini-courses & WorkshopCoxeter Groups Meet Convex GeometryAugust 13–17 and 20–22, 2012, UQAMSponsored by LaCIM

Organizers:Christophe Hohlweg (UQAM), Jean-Philippe Labbé(UQAM), Carsten Lange (FU Berlin), Vivien Ripoll(UQAM)Lecturers:Matthew Dyer (Notre Dame), Christophe Hohlweg,Carsten Lange, Vincent Pilaud (École Polytechnique)Number of participants: 30There are numerous examples of relations betweenconvex geometry and Coxeter groups, the most knownprobably being the construction of the Tits cone. Dur-ing these last years, many interesting other exampleshave been thoroughly studied, among them: general-ized associahedra and permutahedra of finite reflectiongroups; Cambrian fans; brick polytopes and multiasso-ciahedra; imaginary cones and infinite root systems.

These nice encounters between Coxeter groups andconvex geometry have two main consequences: wemanage to understand better the combinatorics and ge-ometry of Coxeter groups by encoding some of theircharacteristics in polytopal or more general convexconstructions; we also obtain new families of interest-ing polytopes, which is very useful in convex geometrysince such families are fairly rare.

The aim of this meeting was to bring together expertsand interested people from both communities, in order

that they learn from one another and discuss togethernew avenues that can be explored. The first week of themeeting was dedicated to minicourses, while the sec-ond week was organized to encourage collaborationsand discussions.

About 30 researchers coming from Europe (France,Italy), Australia, or North America (Canada and USA)attended both the minicourses and the workshop. Wewere very pleased to see that the objectives we set werereached: many collaborations started during this meet-ing, and a second “Coxeter groups Meet Convex Geom-etry” meeting will be organized within two years mostcertainly in Europe.

Infinite-Dimensional Lie Theory: Algebra,Geometry and CombinatoricsA CRM–Fields Institute WorkshopAugust 21–24, 2012, CRM

Organizers:Joel Kamnitzer (Toronto), Michael Lau (Laval)Speakers:Ibrahim Assem (Sherbrooke), Bojko Bakalov (NorthCarolina State), Ivan Dimitrov (Queen’s), Christo-pher Dodd (Toronto), Alex Feingold (Binghamton),Dennis Gaitsgory (Harvard), Nicolas Guay (Alberta),Sam Gunningham (Northwestern), Andrew R. Lin-shaw (Brandeis), Pierre Mathieu (Laval), Ivan Mirkovic(UMass Amherst), Dinakar Muthiah (Brown), ShifraReif (Michigan), Hadi Salmasian (Ottawa), HughThomas (New Brunswick), Peter Tingley (MIT & Loy-ola), Jethro van Ekeren (MIT & IMPA)Number of participants: 42Infinite-dimensional representations of Lie algebrasand related structures play a vital role in a broad swathof modern mathematics, including vertex algebra the-ory, quantum groups, quivers and cluster algebras,geometric representation theory, conformal field the-ory, and the Langlands programme. The jointly spon-sored CRM–Fields workshop brought together an en-ergetic group of more than 40 researchers approachingthe subject from a variety of algebraic, geometric, andcombinatorial points of view.

The first day of the conference featured combinatorialaspects of infinite-dimensional Lie theory. Ivan Dim-itrov explained how some completely elementary com-binatorial objects, inversion sets, can be used to un-derstand difficult geometric and combinatorial prob-lems like the vanishing of the cup product on coho-

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mology of flag varieties in Bott–Borel–Weil, and thedetermination of Littlewood–Richardson coefficients.Hugh Thomas presented a natural bijection betweencertain subcategories of representations of the path al-gebra of a Dynkin quiver and elements of the corre-sponding Weyl group. Ibrahim Assem introduced thenotion of a cluster automorphism and connected thisdefinition with the mapping class group of marked,oriented Riemann surfaces. Peter Tingley and DinakarMuthiah gave well-motivated introductions to the sub-ject of affine Mirkovic–Vilonen polytopes and howthey give a dictionary between Lusztig data associatedwith crystal bases.

The second day of the conference focused on vertexalgebras and their applications. Pierre Mathieu gavea super-extension of Jack polynomials, eigenfunctionsof the Sutherland Hamiltonian that parametrize singu-lar vectors in highest weight modules of the VirasoroLie algebra. Andy Linshaw discussed a vertex operatoranalogue of Hilbert’s theorem on finite generation ofinvariant rings under a reductive group action. Jethrovan Ekeren presented his recent results on modularinvariance of spaces of twisted characters for vertexsuperalgebras of nonintegral conformal weight. BojkoBakalov used the total descendent potential, a gener-ating function for Gromov–Witten invariants, to givea McKay-like relation between Kleinian singularitiesand representations of W -algebras. Alex Feingold usedvertex operator techniques to calculate affine branch-ing rules for inclusions given by Dynkin diagram fold-ing.

The final two days of the conference emphasized ge-ometric representation theory, Lie supergroups, andLie superalgebras. Dennis Gaitsgory outlined the proofof the geometric Langlands conjecture for GL(2), tak-ing care to point out the easy and difficult parts of theproof along the way. Sam Gunningham explained re-sults concerning the cohomology of the character va-riety of a reductive group. Chris Dodd gave a quickreview of Nakajima quiver varieties before describ-ing a way to categorify Lie algebra actions on quivervarieties using D-modules. Ivan Mirkovic presentedLusztig’s conjectures in modular representation theoryand explained how to resolve them using localization,and Nicolas Guay explained how to construct vertexoperator representations for Yangians associated withaffine Lie algebras. Hadi Salmasian surveyed analyticproperties of infinite-dimensional Lie supergroups andshowed how to construct some of their unitary rep-

resentations, and Shifra Reif presented her results ondenominator identities for affine Lie superalgebras atcritical level and some of their interesting applications.

One of the goals of this jointly sponsored CRM–Fieldsconference was to bring together the Lie theory com-munity of central Canada. It is a tribute to the qual-ity and quantity of Lie theory in the region that sucha high-quality conference could be held at the CRMwith a solid majority of participants arriving from uni-versities in Ontario, Québec, and the northeast USA.A remarkable feature of the conference was the rela-tive youth of the participants. Seven of the sixteen in-vited speakers were graduate students or postdoctoralfellows. They and a number of enthusiastic audiencemembers made it a memorable week filled with somefantastic mathematics.

ColloquiumEntretiens Jacques-CartierMathématiques appliquées à la gestion desrisquesNovember 19–20, 2012, Lyon 1Sponsored by the CNRS, the CRM, ISFA (Lyon 1),AMIES, and the Mprime network

Organizers:Christophette Blanchet-Scalliet (École Centrale deLyon), José Garrido (Concordia), Laurent Habsieger(CNRS & CRM), Stéphane Loisel (Lyon 1), ManuelMorales (Montréal), Pierre Ribereau (Lyon 1)Speakers:Patrice Bertail (Paris Ouest), Juliette Blanchet (EPFL),Nicolas Brisebarre (ÉNS Lyon), Rama Cont (CNRS &LMPA), Anne-Béatrice Dufour (Lyon 1), Bruno Dupire(Bloomberg), Nicole El Karoui (UPMC), Max Fein-berg (INRA-Paris), Alexis Hannart (CNRS & IFAECI),Monique Jeanblanc (Évry), Jacques Légaré (Montréal),Marc-André Lewis (CDPQ), Étienne Marceau (Laval),Guy Métivier (Bordeaux 1), Pietro Millossovich (City,London), Didier Sornette (ETH Zürich), Leroy Stone(Montréal)Les vingt-cinquièmes Entretiens Jacques-Cartier sesont tenus à Lyon les 19 et 20 novembre 2012, et plusde 50 participants étaient présents. Les organisateursde la France étaient Christophette Blanchet-Scalliet,Stéphane Loisel et Pierre Ribereau, et les organisa-teurs du Québec étaient José Garrido, Laurent Hab-sieger et Manuel Morales. Plus globalement, les Entre-tiens Jacques-Cartier sont organisés chaque année à lafois par des Français et des Canadiens. Leur vocation

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est de rapprocher des intervenants issus de milieux quine se côtoient pas habituellement. Ils sont articulés au-tour de quatre grands axes : économique et politique,scientifique, social et culturel.

Le but de ce colloque était d’être un lieu de rencontreoù les groupes de recherche industriels et académiquespourraient trouver un environnement propice à la dis-cussion scientifique et aux échanges interdisciplinairessur le thème de la gestion quantitative des risques (enparticulier actuariels, financiers, climatiques, environ-nementaux, de sûreté des calculs, sanitaires et biotech-nologiques). L’objectif principal du colloque était doncde rapprocher ces deux types d’acteurs et d’encouragerles interactions entre eux: d’un côté, les interven-tions faites par des chercheurs industriels ont donnéun aperçu des problèmes d’actualité, des outils et desméthodes utilisés en pratique, et de l’autre, la partici-pation des chercheurs universitaires a apporté à la dis-cussion les nouvelles méthodes et modèles récemmentdéveloppés.

Les sessions et tables rondes du colloque portaient à lafois sur la modélisation de ces risques, sur les mesuresutilisées pour les quantifier, sur le risque de modèle,sur les techniques d’estimation et aussi sur les prob-lèmes d’optimisation liés à l’atténuation ou au trans-fert de ces risques. La capacité de réaction rapide étantsouvent clé en gestion des risques, les problématiquesde détection de changement de tendance ont aussi étéabordées, notamment pour les risques de longévitéet climatiques. Ces questions sont intéressantes nonseulement pour les entreprises, mais aussi pour leschercheurs universitaires qui y trouvent une source denouveaux défis mathématiques.

Les intervenants provenant de ces différents champsdisciplinaires ont pu constater les similitudes et com-plémentarités de leurs approches respectives. Ainsil’un des organisateurs (Manuel Morales) a monté unprojet intitulé “Nouvelle approche de la théorie dela ruine et application en toxicologie” avec d’autreschercheurs français et canadiens, qui a été déposéauprès du Fonds France-Canada pour la Recherche.

ColloquiumEntretiens Jacques-CartierAventures en physique mathématiqueNovember 19–21, 2012, Lyon 1Sponsored by the CNRS, the CRM, the Université Lyon1, the Université de Savoie, the Laboratoire d’Annecy-le-Vieux de Physique Théorique, and the FédérationMSIF

Organizers:John Harnad (Concordia), Claude Roger (Lyon 1), PaulSorba (CNRS & LAPTH), Luc Vinet (Montréal)Speakers:Marco Bertola (Concordia), Robert Brandenberger(McGill), Simon Caron-Huot (Niels Bohr), MatthiasChristandl (ETH Zürich), Sylvie Corteel (CNRS &LIAFA); Luminiţa-Iona Cotîrlă (Babeş-Bolyai), ThierryDauxois (CNRS & Lab./ phys./ ENS Lyon), JamesDrummond (CNRS & LAPTH), Bertrand Eynard(CEA/Saclay), Patrick Ferrari (Bonn), Vincent Genest(Montréal), Yves Grandati (Lorraine), Mihail Mintchev(INFN & SNS Pisa), Alexei V. Penskoi (IU Moscow),Yvan Saint-Aubin (Montréal), Vyacheslav Spiridonov(JINR), Herbert Spohn (TU München), Thomas Strobl(Lyon 1), Serge Tabachnikov (Penn State), LaurentVuillon (Savoie), Oleksiy Zhedanov (Donetsk IPE)Many of the most important and fruitful mathemati-cal theories originated in physical problems. This re-lationship is well known but new and spectacular de-velopments have illustrated it during the last twentyyears. On the other hand modern physics has alwaysneeded mathematical tools and models and must fol-low the progress of the mathematical sciences. Thegoals of this conference were to gather mathematiciansand physicists around some common themes and es-sential results, and to tighten the already existing con-nections between Québec scientists and the scientistsin the Rhône-Alpes region. Here is the list of lecturesthat took place at the conference.• Solitons: revisiting old questions and recent experi-

ments (T. Dauxois)• Physical and mathematical aspects of quantum wires

(M. Mintchev)• Instances of supergeometry in mathematical physics

(T. Strobl)• Proof of the BKMP conjecture: relating topological

strings to matrix models (B. Eynard)• Pentagram map, twenty years after (S. Tabachnikov)

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• From geometry to inhibitors: the story of protein-protein interfaces viewed under the GEMINI soft-ware (L. Vuillon)

• Floquet theory, inflationary cosmology and Ander-son localization (R. Brandenberger)

• Eigenvalue distribution of reduced density matrices(M. Christandl)

• Free energy fluctuations for directed polymers atpositive temperature (P. Ferrari)

• The principal indecomposable representations of theTemperley–Lieb algebra and their physical applica-tions (Y. Saint-Aubin)

• Combinatorics, orthogonal polynomials and ASEP(S. Corteel)

• Recent progress in scattering amplitudes (J. Drum-mond)

• Riemann-Hilbert problems: a tool of many uses (M.Bertola)

• Elliptic hypergeometric functions, superconformalindices, and integrable systems (V. Spiridonov)

• The Kardar-Parisi-Zhang equation and its universal-ity class (H. Spohn)

• Classical orthogonal polynomials corresponding tothe operators of Dunkl type (O. Zhedanov)

• Yang-Mills models in four dimensions: a new kind ofintegrable systems (S. Caron-Huot)

• New classes of harmonic univalent functions (L.-I.Cotîrlă)

• The algebra of dual 1-Hahn polynomials and theClebsch-Gordan problem of the quantum algebrasl(2) at q = −1 (V. Genest)

• New rational extensions of solvable potentials withfinite bound state spectrum and enlarged shape in-variance (Y. Grandati)

• Spectral geometry and mathematical physics jointquest for extremal metrics (A. V. Penskoi)

SUMM 2013Seminars in Undergraduate Mathematics inMontréalJanuary 25–27, 2013, UQAMSponsored by Concordia University, McGill Univer-sity, Université de Montréal, Université du Québecà Montréal, STUDC, the CRM, the ISM, Maplesoft,SUMS, MASSA, and the AESS (UQAM)

Organizers:Jean-François Arbour (UQAM), Geoffroy Bergeron(Montréal), Mathilde Gerbelli-Gauthier (McGill), LéoBelzile (McGill), Kevin Shao (Concordia)

Speakers:José Garrido (Concordia), Christian Genest (McGill),Christophe Reutenauer (UQAM), Robert Seiringer(McGill), Luc Vinet (Montréal)Student Speakers:Jean-François Arbour, Léo Belzile, Younes Ben-Ghabrit(UQAM), Geoffroy Bergeron, Carolyn Campbell(McGill), Simon Chatelain (McGill), Mathilde Gerbelli-Gauthier, Jonathan Godin (Laval), Asad Haris (McGill),Nicole Keating (McGill), Aditya Kumar (McGill), JeanLagacé (Montréal), Olivier Martin (McGill), ThomasNg (McGill), Laurent Pelletier (Laval), Michael Snarski(McGill), Matthew Stevenson (McGill), Mashbat Suzuki(McGill)Number of participants: 97Depuis maintenant quatre ans, les Séminaires universi-taires en mathématiques à Montréal se font un devoirde rassembler les étudiants québécois passionnés parles mathématiques et la statistique dans la métropole.Se faisant, l’organisation les encourage à échanger en-tre eux et transmettre leur passion pour une brancheou une autre de leur discipline d’étude dans une am-biance décontractée. L’évènement vise donc à pro-mouvoir les mathématiques, favoriser les échangesentre étudiants de premier cycle en mathématiques,créer des liens entre les différentes universités de lamétropole et initier la communauté académique de de-main au partage des connaissances.

L’édition 2013 aura été marquée par le retour des Sémi-naires à l’UQAM et le retour des activités du vendredisoir, permettant des rencontres entre étudiants dansun contexte plus convivial. Cette année, les organisa-teurs se sont fait un devoir de collecter des statistiquessur l’évènement qui serviront d’indicateurs-clés pourla prochaine édition. C’est ainsi que 83 participants, unnombre premier, incluant un groupe de 7 étudiants deQuébec, sont venus échanger autour d’exposés étudi-ants et de quatre conférences plénières, avec un con-férencier invité de chaque université et, cette année,une présentation sur les opportunités de financementet sur les groupes de recherche, faite par le directeur del’ISM, Christian Genest. Chaque année, les conférencesplénières constituent une attraction majeure des Sémi-naires. Nous avons eu l’honneur d’accueillir cette an-née José Garrido, Luc Vinet, Christophe Reutenaueret Robert Seiringer. L’expertise de ces conférencierspermit aux participants de s’initier à des sujets depointe en mathématiques; elle favorisa aussi la création

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de liens entre la communauté universitaire actuelle etcelle de demain.

L’évènement se déroula sans anicroche, et la sat-isfaction manifeste des participants a fait honneuraux nombreux bénévoles et aux organisateurs. Noussommes très fiers de la participation étudiante, del’enthousiasme des conférenciers et de la diversité desprésentations étudiantes de cette année. Le bilinguismede l’évènement, reflétant la réalité de la communautéuniversitaire montréalaise, a été maintenu, avec no-tamment l’introduction de diapositives dans la languecomplémentaire pour les exposés bilingues. Nous es-pérons que ces Séminaires sauront former et intéresserles jeunes chercheurs de demain.

Le comité d’organisation tient à remercier les institu-tions qui lui ont apporté un soutien financier (et quisont mentionnées ci-dessus). L’équipe tient égalementà souligner la participation des gens de l’UniversitéLaval, qui ont assisté aux Séminaires grâce au soutienfinancier du STUDC, le comité étudiant de la Sociétémathématique du Canada.

2013 Montréal–Toronto Workshop inNumber Theoryp-Divisible GroupsApril 18–19, 2013, CRMSponsored by CICMA

Organizers:Eyal Z. Goren (McGill), Stephen S. Kudla (Toronto)Speakers:Dylan Attwell-Duval (McGill), Francesca Bergam-aschi (Milano & Concordia & McGill), Amy Cheung(McGill), Eyal Z. Goren, Andrew Fiori (McGill), StevenS. Kudla, Luiz Takei (McGill), Patrick Walls (Toronto),Ying Zong (Toronto)Number of participants: 42The Montreal Toronto workshops in number theoryare a joint enterprise of the Centre de recherchesmathématiques in Montreal and The Fields Institute inToronto. The meetings are run twice a year as work-shops focused on a particular topic in number theory.One of their main goals is to foster scientific relation-ships between the Montreal number theory commu-nity (including the Université Laval in Québec City andthe University of Vermont) and the Toronto numbertheory community (including McMaster University).The workshops have been very successful instructionalevents, unique within the scope of the activities of the

research institutes. A secondary goal is to allow stu-dents to develop skills for making presentations; thebackground talks at the workshop are given by gradu-ate students and postdocs.

The fifth meeting was devoted to the topic of p-divisible groups or Barsotti-Tate groups. These ob-jects have become an indispensable tool in many ar-eas in arithmetic geometry, for example in the study ofShimura varieties, automorphic representations, Ga-lois representations, and variations of zeta functions.Their usefulness keeps extending into other domains.The workshop attempted to give an overview of thesubject, starting from the very first definitions andresults (going back 50 years or so) and ending withsome of the most current topics of interest, such asRapoport-Zink spaces and Kisin modules. As with pre-vious meetings, the level of presentations was excep-tionally high and the participants indeed were able toget a panoramic view of the subjects, as much as canbe done in 10 hours.

As with previous workshops, we have madethe content of the talks available to the pub-lic. The notes of the present workshop can befound at http://www.math.mcgill.ca/goren/Montreal-Toronto/Montreal-Toronto.5.html. The detailed pro-gram was as follows: Dylan Attwell-Duval (Defini-tions and main examples); Luiz Takei (Witt vectors);Patrick Walls (Dieudonné modules); Andrew Fiori(Classification of p-divisible groups up to isogeny);Ying Zong (Deformations, crystals and Grothendieck-Messing theory); Amy Cheung (The Serre-Tate theo-rems); Francesca Bergamaschi (Kisin Modules); SteveKudla (Stratification of unitary Shimura varieties);Eyal Goren (Stratifications of moduli spaces and p-adicuniformization).

Adventures in SuperspaceApril 19–20, 2013, McGillSponsored by the Mathematical Physics Laboratory

Organizers:Robert Brandenberger (McGill), Jim Gates (Maryland),Martin Rocek (Stony Brook)Speakers:Tirthabir Biswas (Loyola), Cliff Burgess (McMaster),Bernard de Wit (Utrecht), Michael Duff (ImperialColl.), Dan Freedman (MIT), Jim Gates, Renata Kallosh(Stanford), Ulf Lindstrom (Utrecht), Martin Rocek,Warren Siegel (Stony Brook), Kelle Stelle (Imperial

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Coll.), Peter van Nieuwenhuizen (Stony Brook), An-toine van Proeyen (KU Leuven)Number of participants: 20This workshop was organized to celebrate the contri-butions of Professor Marcus Grisaru to the field of su-pergravity. We were happy that all of the senior ex-perts in the field of supergravity who together withMarcus helped create the field accepted our invita-tion to come to this workshop. In particular, ProfessorsJim Gates (recently awarded the US National Medalof Science), Martin Rocek, and Warren Siegel partic-ipated. Together with Grisaru, the four are authorsof the ground-breaking textbook “Superspace, or Onethousand and one lessons in supersymmetry.” Profs.de Wit, Duff, Freedman, Lindstrom, Mezincescu, Stelle,Townsend, van Nieuwenhuizen and Van Proeyen areall senior experts in the field of supergravity and haveall at some point collaborated with Marcus Grisaru. Itwas a rare treat to have all of these experts in the sameplace at the same time. Here is a list of some of thetalks.• M. Grisaru & the Eden of Supergravity (J. Gates)• Gauge multiplets and gauging in D=2 sigma-models

(M. Rocek)• Anomaly multiplets, regrisaruzation & solitons (P.

van Nieuwenhuizen)• 3D strings: an open-and-shut case (P. Townsend)• Generalized Kähler geometry and sigma models (U.

Lindstrom)• Superconformal symmetry and higher-dimensional

Lagrangians (A. van Proeyen)• A Superspace Odyssey (B. de Wit)• UV properties of N=8 and N=4 supergravities (R.

Kallosh)• UV divergences in maximal and half-maximal super-

gravity (K. Stelle)• The holographic dual of F-maximization (D. Freed-

man)• Vanish without a trace (M. Duff)• Towards consistent nonlocal theories of gravity (T.

Biswas)• Supersymmetric cancellations without superpart-

ners: having your cake and eating it too (C. Burgess)

Spring School7th Montréal Scientific Computing DaysMay 13–15, 2013, CRMSponsored by the Applied Mathematics Laboratory

Organizers:Emmanuel Lorin de la Grandmaison (Carleton), RobertOwens (Montréal)Invited Speakers:Xavier Antoine (Lorraine), Michael Griebel (Bonn),Doron Levy (Maryland)Other Speakers:Gustavo Avila-Blanco (Queen’s), Muhammad Awais(Victoria), Tucker Carrington (Queen’s), Alexan-dre Desfossés Foucault (Montréal), François Fillion-Gourdeau (Montréal), Denis F. Hinz (McGill), AzadehJafari (Montréal), Tae-Yeon Kim (McGill), LahcenLaayouni (Al Akhawayn), David Lapierre (Montréal),Felicia Magpantay (York), Mike McLeod (Ottawa),Maryam Namazi (CCCMA), David Shirokoff (McGill),Ilyssa Summer (Arizona State), Alexandra Tcheng(McGill), Jinming Wen (McGill)Number of participants: 67The Montréal Scientific Computing Days (MSCD) isa workshop quite unique in its format in Québec.This meeting covers a wide spectrum of mathemati-cal themes centred around scientific computing: theanalysis of partial differential equations, numericalanalysis, computational sciences, high performancecomputing, as well as numerous application areas inphysics, biology, medicine, finance, etc. As far as is rea-sonably possible, the MSCD tries to maintain a goodbalance between theory and applications. The work-shop that took place in May of this year was the sev-enth in a series that has enjoyed great success in thepast, thanks in particular to the high quality of the in-vited speakers (whose course notes have been madeavailable online to participants) and to the active par-ticipation of the graduate students and postdocs. Thisyear 67 people registered for the workshop, and al-though the great majority of participants came fromuniversities in Québec and Ontario, others came fromas far afield as Morocco, Texas, and British Columbia.

The MSCD is an ideal opportunity for students andother researchers from various scientific communi-ties (physicists, mathematicians, computer scientists,etc.) to interact in a welcoming and informal setting.The workshop also gives graduate students and post-docs the opportunity of taking short courses, each ofthree hours’ duration and pitched at an accessible level,and given by researchers of international stature. Thisyear’s invited speakers were Xavier Antoine, MichaelGriebel, and Doron Levy. Prof. Antoine delivered a se-ries of talks entitled How to truncate a PDE problem set

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in an unbounded domain: the example of the Schrödingerequation.

The goal of this introductory course was to give anoverview of some of the techniques that can be usedto truncate the spatial domain on which is defined apartial differential equation in an attempt to minimizethe effect of the truncation operation. At the heart ofthe presentations was a detailed treatment of absorb-ing boundary condition methods and others for tack-ling general problems with particular application tothe Schrödinger equation. This equation, which hasmany applications in physics and engineering, leads todifficult questions concerning the mathematical con-struction of absorbing boundary conditions as well astheir numerical approximation. In particular, even inthe simplest case, it is necessary to develop nontrivialsolutions to get numerical schemes with suitable prop-erties (like stability).

In this course, Prof. Antoine discussed the followingquestions, of increasing difficulty:• the free space one-dimensional Schrödinger equa-

tion;• how to take into account potentials in 1d;• how to extend the methods to 1d nonlinear prob-

lems;• two-dimensional problems; and• inclusion of potentials and nonlinearities.Prof. Griebel’s mini-course of three lectures was onthe theme of generalized sparse grids. Efficient ap-proximations for multivariate functions can be de-rived from a one-dimensional multilevel representa-tion of a function (hierarchical basis, generating sys-tem, (pre)wavelet system, Fourier series, eigenfunctionseries, or similar methods) by a product construction toobtain a multilevel system for the many-dimensionalcase and a subsequent proper truncation of the re-sulting series expansion. This leads to so-called sparsegrids, which promise to cope with the curse of di-mensionality in conventional product discretizations,at least to some extent. First, Prof. Griebel discussedregular sparse grids and their approximation and costcomplexities. Besides regular sparse grids, one can alsoconstruct (by means of an optimization process) spe-cific problem-dependent sparse grids that exhibit opti-mal asymptotic complexity estimates for various situ-ations, error norms, and regularity assumptions. Prof.Griebel presented such methods in detail and, in con-clusion, discussed various applications.

In recent years, mathematical models have been play-ing an increasing role in cancer studies. The under-lying complexity of the biological processes requiresresearchers to use mathematical models of differenttypes, including discrete and continuous models, de-terministic and stochastic models, and models withtime delays. The lectures by Prof. Doron Levy were onnumerical methods for mathematical models of cancerdynamics and on agent-based models (ABM) in can-cer. In the former topic, we learned about numericalmethods for delayed differential equations and numer-ical methods for nonlinear time-dependent PDEs. Inthe latter topic, Prof. Levy discussed ABMs for solidtumor growth and the Roeder model of stem cells. Hewent on to explain how to pass from ABMs to PDEsand concluded his series of talks with a presentationof related techniques, including crime models and atechnique for deriving various Fokker-Planck equa-tions from stochastically interacting particles. The de-tailed slides of the mini-courses given by the three in-vited speakers may be downloaded from http://www.

crm.umontreal.ca/Comp13/diapo_e.shtml.

As well as being an opportunity for graduate stu-dents and post-docs to keep abreast (through the mini-courses) of some of the latest research directions incomputational applied mathematics, the MSCD also af-fords a unique opportunity for these students to makean oral presentation on the results of their research,both to their own peer group and to the wider ap-plied mathematics community in Québec. In all 16 suchpresentations were given during the workshop, and inkeeping with tradition, it was expected that a prize (inthe form of a SIAM book token) would be awardedfor the best presentation. The overall standard of stu-dent and postdoc talks, however, was very high andthe choice of the most deserving candidate was ex-ceptionally difficult. The scientific committee (com-posed of Yves Bourgault, from the University of Ot-tawa, Emmanuel Lorin de la Grandmaison, and RobertG. Owens) decided that the prize should be awardedex aequo to Alexandre Desfossés Foucault, Felicia Mag-pantay, and Alexandra Tcheng. These three are warmlycongratulated on the excellence of their research andthe clarity and impact of their presentations.

WorkshopN = 2 Jeometry and ApplicationZ Part IIMay 22–24, 2013, McGill

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Organizers:Keshav Dasgupta (McGill), Jihye Seo (McGill), Jo-hannes Walcher (McGill)Speakers:Richard Eager (Kavli Inst.), John Harnad (Concor-dia), Simeon Hellerman (Kavli Inst.), Jacques Hurtubise(McGill), Kazunobu Maruyoshi (Caltech), DomenicoOrlando (CERN), Chan Youn Park (Caltech), JaewonSong (UC San Diego), Masahito Yamazaki (Princeton)Number of participants: 33This workshop was a second installment of N =2 Jeometry and ApplicationZ. Last year’s partic-ipants, Kenneth Intriligator (UC San Diego) andNathan Seiberg (IAS), acknowledged the first install-ment in their preprint “Aspects of 3d N = 2 Chern-Simons-Matter Theories,” which appeared this Mayon arxiv, as arXiv:1305.1633. It was also mentionedin the New York Times. This year’s focus was moremathematical, featuring superconformal index count-ing, Vasiliev’s theories, superconnection constraintequations, Chern-Simons theory, Sasaki-Einstein, lensspace, and topological string.

The theme of the workshop was 4-dimensional super-symmetric field theories. There have been lots of inter-est and progress recently in this area. Most pioneer-ing works are a new set of theories called “class S,”which is obtained by wrapping M5 branes on a Rie-mann surface, by Gaiotto-Moore-Neitzke and Alday-Gaiotto-Tachikawa correspondence relating a certainclass of 4-dimensional N = 2 superconformal theo-ries to 2-dimensional (bosonic) conformal theories, and“Nekrasov-Shatashvili” relation between Ω-deformedN = 2 theories and quantum integrable systems.

Equipped with cluster coordinates and bipartite net-works, studies of N = 2 theories are gaining evenlarger momentum these days, signaling potential rel-evance to brane tilings in N = 1 quiver and scatteringamplitudes of N = 4 super Yang-Mills theory. Theseare pioneered by Xie, Franco, Yamazaki, Cachazo,Arkani-Hamed et al. A close relationship between su-persymmetric field theories and totally non-negativeGrassmannians is studied with varying amount of su-persymmetry 1 ≤ N ≤ 8.

The workshop also included supersymmetric field the-ories in other dimensions, and with different amountsof supersymmetry. There were many discussions ofstring compactification, Vasiliev theory, AdS/CFT, S-dualities, Wilson loops, etc. The organizers providedan interface for interactions between the math and

physics communities. There were two math reviewtalks by local researchers and eight physics talks fromexternal speakers.

According to Chan Youn Park, M2 branes between twoM5 branes wrapping a Seiberg-Witten curve are de-scribed by a 2d N = (2, 2) Landau Ginzburg modelwith chiral fields and superpotential. He discussed howto construct spectral networks to analyze the BPS spec-tra and their wall-crossing in his talk “Spectral net-work and BPS spectrum of SCFT.” He studied exam-ples of spectral networks to illustrate how to utilizethe results in identifying SCFTs that have different de-scriptions. He performed a similar analysis and com-puted central charges and gauge/flavour charges forthe Argyres-Douglas theory, an interacting SCFT the-ory with 4d and N=2 with mutually nonlocal masslessstates.

The TN theory is a N = 2 SCFT theory obtainedby compactifying a 6d (2,0) theory of M5 branes on asphere with three full punctures with SU(N)3 flavoursymmetry, with no Lagrangian description. KazunobuMaruyoshi gave a talk entitled “N = 1 Dynamicswith TN superconformal field theories,” in which heexplained the coupling of TN ’s to N = 1 vector multi-plets. By reducing Csaki–Schmaltz–Skiba–Terning du-ality, he and his collaborators obtain a duality be-tween conventional theory (such as supersymmetricQCD) and non-conventional theory. He showed thatthe theory exhibits confinement, superconformal, andAbelian Coulomb phases, depending on the mannerof coupling TN theories to N = 1 vector multiplets.In particular, a N = 1 SU(N) gauge theory coupledto two TN theories, which flows to a superconformalfixed point, has dual descriptions with gauge singletfields, and this leads to, by Higgsing, a new duality ofN = 1 SQCD with Nf = 2N .

Masahito Yamazaki and Richard Eager discussed in-dex computation, to test S-duality and AdS/CFT cor-respondence. Although the Lagrangian description isoften used in Feynman diagrams in QFT, it is not fun-damental (as seen from recent works by Freddy Cac-hazo and Nima Arkani-Hamed). Gauge symmetry isalso not fundamental: it is considered to be a redun-dancy and it can even change under Seiberg duality.In Yamazaki’s talk “4d N = 2 Lens indices fromS-duality,” he asks whether (Gaiotto-like) S-duality isfundamental to QFT. “Is S-duality powerful enough tocharacterize a theory completely?” might be too ambi-tious a question and ambiguous. So he tries to answer

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the following question: “Is S-duality powerful enoughto characterize the lens space index completely?” Hefinds that the lens index, which is a partition functioncomputed on S1 × S3/Zr , is almost completely deter-mined by S-duality and that S-duality is indeed pow-erful.

The superconformal index is the partition function ofthe (1+d)-dimensional superconformal field theory onS1 ×Sd with supersymmetric boundary conditions. Itis also the generating function of the number of op-erators weighted by their fermion number. The indexis independent of the exact marginal deformations ofthe theory, and is calculable if the UV Lagrangian isknown. In a talk titled “Superconformal indices in di-mensions 2, 3, and 4,” Eager considered the gauge the-ory index, the gravity index, and the elliptic genus inorder to check the AdS/CFT correspondence. He com-puted the superconformal index of M2 branes prob-ing the cone over an arbitrary Sasaki–Einstein seven-manifold and that of a D3 brane probing the Calabi–Yau cone. The index should be invariant under Seibergduality and AdS/CFT. His talk also led to a discus-sion about the spectrum of Sasaki–Einstein manifoldsand solving Heun’s equation. The second-order equa-tion reduces to a linear equation for the BPS spectrum.There were questions about the choice of contour.

We had two talks related to the Nekrasov’s partitionfunction and the Ω deformation. The Ω backgroundwas introduced by Nekrasov to regularize the 4d in-stanton partition function and reproduce the resultsof Seiberg-Witten. The Ω deformation is controlled bytwo parameters ε1,2 and various interesting limits ex-ist, such as topological string on Calabi–Yau, Samson’slimit (quantum integrable model), refined topologicalstring, and AGT.

Domenico Orlando talked about how the Ω defor-mation can be understood from the viewpoint ofold-fashioned string theory, based on Neveu-Schwarzfields. His talk was entitled “the Ω deformation fromstring and M-theory.” It allowed one to understandlocalization in geometric terms. The Ω deformationis an effective 4d action for the fluctuations of theM5-branes. The parameter ε1,2 appears as a non-commutativity parameter in the quantum spectralcurve, and there appears a Riemann surface embeddedin a non-commutative complex plane.

In a talk entitled “The ABCDEFG of 4d/2d Corre-spondence,” Jaewon Song explained how to obtain the

BCFG group (in 2d and 4d theories) from ADE (in 6dtheory). In simple language, folded Lie algebras can beobtained by various foldings as a 6d theory is compact-ified onto 2d and 4d theories. This work was inspiredby Rastelli et al’s work on the correspondence between4d index and 2d TQFT. There were many discussionsabout the scheme-dependence of the Nekrasov parti-tion function.

There were two talks related to the Chern-Simonstheory. Masahito Yamazaki talked about “3d Chern-Simons from M5-branes.” He discussed 3d theoriescoming from the 6d theory of M5 branes. He discussedthe partition function of 5d N = 2 SYM, which is thedimensional reduction of the 6d theory. By supersym-metric localization the 5d partition function reduces tothat of the 3d pure Chern-Simons theory. This workhad two goals: one is to improve the conceptual under-standing of AGT (Alday-Gaiotto-Tachikawa), which isa 4d-2d correspondence, and the other is to formulatea 3d-3d equivalence of AGT. There were many discus-sions about the role of the U(1) orbit inside the 6d in-ternal geometry as we compactify the 6d theory into a5d SYM theory.

The talk “Chern-Simons-Matter Theory and its Holo-graphic Dual” (by Simeon Hellerman) was about de-bunking many myths around Vasiliev theory. In hisinvigorating talk, he emphasized the beauty of N =4 SYM and left a famous quote: that physics text-books must discuss N = 4 SYM before they discussMaxwell’s theory of electromagnetism. The biggestproblem with Vasiliev theory and the proposal for itsAdS/CFT dual comes from the counting of degrees offreedom. Hellerman emphasized that Vasiliev theorydoes not have a consistent ultraviolet completion, andde Sitter / CFT is not viable in its current form. It wasvery alarming and insightful in many ways. He men-tioned his work in progress on branes in topologicalstring theory, and there were many questions aboutgravitons built out of open strings, and the possibil-ity of addressing the higher-genus case (beyond S3).Hellerman led an afternoon discussion session and theupshot was that the Chern-Simons theory has no localdegrees of freedom and the correction to the spectrum,if not zero, is very small (exponentially suppressed).

In order to foster more interaction between math-ematicians and physicists, the workshop included 2other mathematical talks. The results have significancefor many recent works in the physics literature on su-perspace null polygonal Wilson loops in supersym-

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metric Yang-Mills theories. In recent computations ofsuper null polygonal Wilson loop amplitudes in super-space by Beisert, He, Vergu, et al, an essential ingredi-ent is the super null line constraint equations, whichprovide the necessary conditions for the “thickenednull line” integrations to be well defined.

Jacques Hurtubise gave a talk entitled “The geome-try of supersymmetric Yang-Mills in four dimensions,”about his work with John Harnad and Steve Shnider onsuperconnection constraint equations. Hurtubise pre-sented the d = 4 results connecting the constraintequations and the field equations for N = 0, 1, 2, 3.Another talk was given by John Harnad, under the titleof “Constraints and field equations for d = 10, N = 1SYM,” presenting the analogous results for d = 10,N = 1, which (by dimensional reduction) also givea simpler derivation of the d = 6, N = 2 and d = 4,N = 4 cases, with a summary of how the twistor cor-respondences extend to arbitrary dimensions. Harnadreviewed the equivalence between the constraint equa-tions and the field equations in the d = 10,N = 1 SYMtheory, underlying Witten’s “super-twistor-like trans-form” and the dimensional reduction procedure thatimplies the corresponding results for d = 6, N = 2and d = 4, N = 4.

The workshop was hosted by the McGill physics de-partment and had the same format as other successfulevents organized by McGill’s Center for High-EnergyPhysics about three to four times a year: Two and a halfdays with several external speakers in a relaxed atmo-sphere with ample time for discussions. Such a formatis of particular benefit for graduate students aroundMontréal, who have the opportunity to meet and inter-act with distinguished scholars in their chosen field ofstudy. Everyone left Montréal looking forward to a fu-ture meeting. This year’s participants were of the opin-ion that our workshop was really lovely, *extremely*stimulating, and informative.

GAP 2013: Geometry And PhysicsMay 30–June 1st, 2013, CRMSponsored by the Perimeter Institute for TheoreticalPhysics, the University of Waterloo Faculty of Mathe-matics, the CRM, and the McMaster University Facultyof Science

Organizers:Marco Gualtieri (Toronto), Spiro Karigiannis (Water-loo), Ruxandra Moraru (Waterloo), Johannes Walcher(McGill), McKenzie Wang (McMaster)

Speakers:Philip Boalch (CNRS; ÉNS), Sergey Cherkis (Arizona),Tamàs Hausel (EPFL), Andrew Neitzke (UT Austin),Lauren Williams (UC Berkeley)Number of participants: 62GAP 2013 consisted of five minicourses, each threehours long, given by Philip Boalch, Sergey Cherkis,Tamás Hausel, Andy Neitzke, and Lauren Williams,to a mixed audience consisting of graduate students,postdoctoral researchers, and senior researchers. Thelonger format meant that speakers could go intogreater depth and cover more of the field than wouldhave otherwise been possible. The common focustopic, that of wall crossing phenomena in modulispaces, also meant that the audience could focus foran extended period of time on a smaller number ofconcepts and their interrelations. The most remarkableoutcomes of the workshop format were emergent re-lationships between the talks that even the speakershad not intended. On many occasions, heated discus-sions erupted during the talks between various expertsamong the speakers and the audience about possibleextensions and applications of the presented results.Indeed, what began as a pedagogical exercise rapidlybecame a real-time research workshop.

Philip Boalch used his lectures as an opportunity to de-scribe an important family of moduli spaces that hasoccupied his research for many years: the wild char-acter varieties. These are moduli spaces of meromor-phic connections on Riemann surfaces, but with irreg-ular singularities. The study of irregular singularitiesand their associated Stokes phenomena have tradition-ally been viewed as highly technical and abstruse, butthrough his recent work Boalch has clarified, general-ized, and significantly extended the theory, exposingits beauty as well as its many applications in mathe-matical physics. In addition to surveying the structuretheory of these spaces, Boalch explained the appear-ance of these moduli spaces in several important areasincluding quantum groups.

Tamás Hausel’s minicourse focused on his recent re-markable computations and conjectures concerningthe Betti numbers of the character varieties that arediffeomorphic to the moduli space of Higgs bundles.These computations were made by expressing thecharacter varieties as algebraic varieties over finitefields and then counting rational points using char-acter formulas for representations of finite groups ofLie type. His results are the culmination of many years

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General Program

of research into the topology of Higgs moduli spaces,and he was able to describe very clearly the train ofthought leading from Hitchin’s original work directlyto his recent papers, as well as the work of Ngo on thefundamental lemma.

Sergey Cherkis, in only three lectures, was able to de-scribe the vast subject of gravitational instantons, cov-ering ALE, ALF, ALG, and ALH spaces, and their beau-tiful explicit constructions as moduli spaces. He de-scribed in a unified manner the various tools whichare used in this story, starting with the ADHM con-struction, Nahm’s equations, and the Nahm trans-form, among others. There was also an introduction totwistor theory, toric geometry, and even tropical ge-ometry. Cherkis’ lecture series was particularly inspir-ing to the graduate students in attendance, who mayhave learned many of the techniques mentioned in hiscourse, but not seen how they are applied to solve deepproblems in mathematical physics.

Andy Neitzke used the opportunity given him by thetriple of lectures to describe his body of work withGaiotto and Moore on Spectral Networks in a com-pletely novel way: rather than focusing on the use ofspectral networks for possibly determining the Hyper-Kähler metric on the moduli space of Higgs bundles,Neitzke focused instead on the potential for finding ex-plicit solutions to Hitchin’s equations. This approachprovided a much more direct and less front-loaded ap-

proach to his recent papers, and was particularly in-spiring to the many people in the audience who studyStokes phenomena and irregular singularities. His lec-tures were also remarkable in the number of openmathematical questions that were posed: the excitingprospect of developing these offshoots, especially theconnection to Lauren Williams’ talks on cluster alge-bras, motivated many questions from the audience.

Lauren Williams presented what is perhaps the clear-est and most straightforward description of cluster al-gebras yet. Starting with startlingly simple combinato-rial setups, she quickly layered these together to obtaina description of the cluster structure on Grassmanni-ans, describing all the major features of the theory ofcluster algebras along the way, including the relationto bordered surfaces, triangulations, ADE quivers, andmutations, among many others. The connections be-tween the various topics touched upon by Williamsand the other talks were surprising to many, includ-ing to the other speakers.

In conclusion, the new format of the GAP 2013 con-ference at the CRM was a surprisingly effective one,not only for student researchers attempting to enterthe field, but also for the senior researchers present,who may not always glean, from the published papers,as many insights as one does when the experts them-selves are teaching their subject.

Colloquium and Seminar Series

The CRM, together with the Institut des sciences mathématiques (the Québec universities graduate mathematicsconsortium), runs two Montréal colloquium series, one in mathematics and the other in statistics (the latter jointlywith GERAD, an operations research centre located in the André-Aisenstadt building). During the academic year,these series offer survey talks on topics of current interest by distinguished mathematicians and statisticians.

CRM–ISM Mathematics Colloquium

In 2012–2013 the colloquium coordinators were Iosif Polterovich (Montréal) and Mikaël Pichot (McGill).

September 14, 2012Robert McCann (Toronto)A glimpse at the differential topology and geometry ofoptimal transportation

September 21, 2012Walter Neumann (Columbia)Geometry of complex surface singularities

October 12, 2012Rupert Frank (Princeton & Caltech)Symmetry and reflection positivity

November 2, 2012Jürg Fröhlich (ETH Zürich)Dissipative motion from a Hamiltonian point of view

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November 16, 2012Konstantina Trivisa (Maryland)On the Doi model for the suspension of rod-like molecules& related equations

November 23, 2012Alexander Gamburd (Graduate Ctr., CUNY)Expander graphs, thin groups, and superstrong approxi-mation

December 7, 2012Yuri Tschinkel (NYU & Simons Found.)Igusa integrals

January 25, 2013Sheila Sandon (CNRS; Nantes)Global rigidity in contact topology

February 1, 2013Elliott Lieb (Princeton)Proof of a 35-year-old conjecture for the entropy of SU(2)coherent states, and its generalization

February 8, 2013Sergei Tabachnikov (Penn State)Pentagram map, twenty years after

February 15, 2013Nilima Nigam (Simon Fraser)Eigenproblems, numerical approximation and proof

March 1, 2013Frithjof Lutscher (Ottawa)Mathematical models for river ecosystems

March 28, 2013Victor Guillemin (MIT)Moser averaging

April 5, 2013Ehud DeShalit (Hebrew)Integral structures in p-adic representations

April 12, 2013Narutaka Ozawa (Kyoto)Quantum correlations and Tsirelson’s problem

CRM–ISM–GERAD Statistics Colloquium

In 2012–2013 the organizing team of the Statistics Colloquium included Mylène Bédard (Montréal), Simon Guil-lotte (UQAM), Abbas Khalili (McGill), Lea Popovic (Concordia), and David A. Stephens (Concordia).

September 21, 2012Fang Yao (Toronto)Regularized semiparametric functional linear regression

October 19, 2012David Madigan (Columbia)Observational studies in healthcare: are they any good?

November 23, 2012Peter Müller (UT Austin)A nonparametric Bayesian model for local clustering

December 14, 2012Raymond J. Carroll (Texas A&M)What Percentage of children in the U.S. are eating ahealthy diet ? A statistical approach

January 18, 2013Victor Chernozhukov (MIT)Inference on treatment effects after selection amongsthigh-dimensional controls

March 22, 2013Hélène Massam (York)The hyper Dirichlet revisited: a characterization

April 12, 2013Arup Bose (ISI Kolkota)Consistency of large dimensional sample covariance ma-trix under weak dependence

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Multidisciplinary and Industrial Program

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Centre de recherches mathématiqes

The main vehicles for the CRM’s efforts in this area are the research networks to which it belongs, principallyMprime, a national network focusing on the mathematics of information technology and complex systems.

The reports are presented in the language in which they were submitted.

Activities of the Multidisciplinary and Industrial Program

6th International Conference onInformation Theoretic Security (ICITS)August 15–17, 2012, MontréalSponsored by the CRM, the Institute for QuantumComputing (University of Waterloo), and INTRIQ (astrategic cluster funded by the FRQNT)

Organizers:Jürg Wullschleger (Montréal), Alain Tapp (Montréal),Claude Crépeau (McGill), Adam D. Smith (Penn State),Olivier Coutu (Montréal)Number of participants: 58The International Conference on Information Theo-retic Security (ICITS) is a conference about all aspectsof information-theoretic security. Its aim is to bring to-gether researchers from all over the world from the ar-eas of cryptography, information theory and quantuminformation. The conference was created as a succes-sor of the “IEEE Information Theory Workshop on The-ory and Practice in Information-Theoretic Security” onAwaji Island, Japan, and takes place every 18 months,alternating between Asia, Europe and North Amer-ica. Previous ICITS conferences were held in Madrid(Spain), Calgary (Canada), Shizuoka (Japan), and Am-sterdam (The Netherlands). ICITS 2012 was held fromAugust 15 to 17, 2012 in Montréal.

As in previous ICITS conferences, the plenary talkswere given by the leading researchers in the field. Oneof the highlights of this conference was the talk by SalilVadhan from Harvard University, who gave a presen-tation about “The Many Entropies of One-Way Func-tions.” The other plenary talks were given by SergeFehr (CWI Amsterdam), Patrick Hayden (McGill Uni-versity), Negar Kiyavash (University of Illinois at Ur-bana-Champaign), Xin Li (University of Washington)and Krzysztof Pietrzak (IST Austria).

The usual process for conferences in Computer Scienceis that all submitted papers first undergo a careful re-viewing process, and all papers that are accepted arenot only presented at the conference, but also appearin the conference’s proceedings. Previous ICITS con-ferences also used this format, but it turned out not tobe optimal for information theorists and physicists. For

this ICITS, the organizers therefore decided to make aspecial “workshop track,” in addition to the more stan-dard “conference track,” where the speakers needed tosubmit only a one-page abstract that will appear in theproceedings. This new format (with both a conferencetrack and a workshop track) was a big success, bothin quality and quantity, and having an additional trackalso increased the number of participants.

Montréal Spring School ofPopulation Genomics and GeneticEdidemiologyMay 27–31, 2013, Collège Jean-de-BrébeufSponsored by Génome Québec, the CHU Sainte-Justine Research Centre, the CRM, the Université deMontréal, and McGill University

Organizers:Luis Barreiro (Montréal), Gillian Greig, Aurélie Labbe(McGill), Damian Labuda (Montréal), Jean-FrançoisLefebvreScientific Committee:Jamie Engert (McGill), France Gagnon (Toronto), MajaKrajinovic (Montréal), Marie-Hélène Roy-Gagnon(Montréal), Julian Little (Ottawa), Erwin Schurr(McGill), Terry Lynn Young (Memorial)Speakers:Anna Di Rienzo (Chicago), Youssef Idaghdour (Mont-réal), Joseph Pickrell (Harvard), Hélène Vézina(UQAC), Ma’n H. Zawati (McGill)Instructors:Alexandre Alcaïs (Paris Descartes), Will Astle (McGill),Luis Barreiro, Guillaume Bourque (McGill), LaurentExcoffier (Bern), Celia Greenwood (McGill), NicolasLartillot (Montréal), Guillaume Lettre (Montréal), LluísQuintana-Murci (Inst. Pasteur), Joseph PickrellNumber of participants: 63The objective of the School was to provide training inrapidly developing disciplines that are becoming in-creasingly important in health sciences, such as sta-tistical genetics, human evolutionary genetics, popu-lation genomics and bioinformatics. The training wasbased on real-data examples from the research of the

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instructors’ laboratories. In one module we also pre-sented genealogical resources specific to Québec.

The school consisted of five days of lectures and com-puter labs. Days 1 and 2 covered introductory con-cepts in human population, medical genomics, and ge-netic epidemiology. Days 3 to 5 consisted of concur-rent sessions in advanced concepts in population ge-nomics/statistical genetics and in genetic epidemiol-ogy. Before attending the school, participants were in-vited to review basic concepts in genetics, epidemiol-ogy, biostatistics and R-programming, by studying in-

troductory courses from previous years that are postedon our web site.

For the 6th edition of the Montréal spring school,there were 47 participants (28 from Québec, 8 fromOntario, 5 from the USA, 3 from Europe, and 3 fromSouth America) and 15 faculty members from Québec,France, Switzerland, and the USA. The school was agreat success this year. Participants really enjoyed thebroad scope of the workshop and found that it pro-vided great networking opportunities. The practicalcomputer component was also greatly appreciated.

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CRM Prizes

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CRM Prizes

The CRM created and administers, either alone or jointly, four of the eight major national prizes in the math-ematical sciences, namely: the CRM–Fields–PIMS Prize, the Prize for Theoretical Physics awarded in collab-

oration with the Canadian Association of Physicists (CAP), the Prize for young researchers in Statistics awardedjointly with the Statistical Society of Canada (SSC), and the CRM André-Aisenstadt Prize awarded to rising youngCanadian stars, selected by the International Scientific Advisory Committee of the CRM. The CRM has investedenormously in time, effort and in its own resources, to propel leading Canadian scientists into the spotlight, givingthem international recognition when they most need it.

CRM–Fields–PIMS Prize 2013 Awarded to Bruce Reed

Bruce Reed

Bruce Reed received his degrees in Mathematics andin Computer Science at McGill University. Follow-ing postdoctoral fellowships and faculty positions inEurope, Canada, and the USA, he joined the facultyof McGill University in 2001: he currently holds theCanada Research Chair in Graph Theory and waselected as a Fellow of the Royal Society of Canada in2009.

Bruce Reed has played a leading role in a broad rangeof research areas in discrete mathematics and theoret-ical computer science. He is best known for his workon areas within graph theory, with many of his most

important contributions being in random structures,graph minors, and graph colouring. The 2013 CRM–Fields–PIMS Prize recognizes his profound contribu-tions to difficult and important problems in the areas ofgraph minors, graph colouring, algorithmic graph the-ory, random graphs, and the probabilistic analysis ofalgorithms. The reader will find a detailed descriptionof Professor Reed’s contributions in the Spring 2013edition of the Bulletin du CRM.

The CRM–Fields–PIMS Prize

This prize was established in 1994 as the CRM–FieldsPrize to recognize exceptional research in the math-ematical sciences. In 2005 PIMS became an equalpartner in the awarding of the prize and its namewas changed to the CRM–Fields–PIMS Prize. A com-mittee appointed by the three institutes chooses therecipient. The previous recipients of the prize areH.S.M. (Donald) Coxeter (1995), George A. Elliott(1996), James Arthur (1997), Robert V. Moody (1998),Stephen A. Cook (1999), Israel Michael Sigal (2000),William T. Tutte (2001), John B. Friedlander (2002),John McKay (2003), Edwin Perkins (2003), Donald A.Dawson (2004), David Boyd (2005), Nicole Tomczak-Jaegermann (2006), Joel S. Feldman (2007), AllanBorodin (2008), Martin Barlow (2009), Gordon Slade(2010), Marc Lewis (2011), and Stevo Todorcevic (2012).

André-Aisenstadt Prize 2013 Awarded to Spyros Alexakis

Dr. Alexakis obtained a B.A. degree from the Univer-sity of Athens in 1999 and a Ph.D. from Princeton Uni-versity, under the supervision of Charles Fefferman, in2005. He held a Clay Research Fellowship as well asa Sloan Fellowship, and has been at the University ofToronto since 2008. Working in the areas of analysisand mathematical physics, alone and with collabora-tors, he has obtained striking results in at least three

different directions. His main contribution, publishedas a research monograph in the prestigious Annals ofMathematics Studies of Princeton University, is a solu-tion to a conjecture of Deser and Schwimmer regard-ing the structure of global conformal invariants. Sec-ondly, together with Klainerman and Ionescu, he madeimportant progress in the understanding of the Kerrsolutions to Einstein’s equations. Finally, jointly with

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Spyros Alexakis

Mazzeo, he obtained deep results concerning minimalsurfaces with bounded Wilmore energy. This impres-sive research is described by Dr. Alexakis himself inthe Fall 2013 edition of the Bulletin du CRM.

The André-Aisenstadt Prize

Created in 1991, the André-Aisenstadt MathematicsPrize is intended to recognize and reward research

achievements in pure and applied mathematics by tal-ented young Canadian mathematicians. This prize con-sists of a $3,000 award and a medal. The recipient ischosen by the International Scientific Advisory Com-mittee of the CRM. At the time of consideration, can-didates must be Canadian citizens or permanent resi-dents of Canada, and no more than seven years fromtheir Ph.D.

The previous recipients of the André-Aisenstadt Prizeare Niky Kamran (1992), Ian Putnam (1993), MichaelWard (1995), Nigel Higson (1995), Adrian S. Lewis(1996), Lisa Jeffrey (1997), Henri Darmon (1997),Boris Khesin (1998), John Toth (1999), Changfeng Gui(2000), Eckhard Meinrenken (2001), Jinyi Chen (2002),Alexander Brudnyi (2003), Vinayak Vatsal (2004), RaviVakil (2005), Iosif Polterovich (2006), Tai-Peng Tsai(2006), Alexander E. Holroyd (2007), Gregory G. Smith(2007), József Solymosi (2008), Jonathan Taylor (2008),Valentin Blomer (2009), Omer Angel (2010), Joel Kam-nitzer (2011), Marco Gualtieri (2012), and Young-HeonKim (2012).

The CRM–SSC Prize 2013 Awarded to Derek Bingham

Derek Bingham

Derek Bingham obtaineda B.Sc. in Applied Mathe-matics at Concordia Uni-versity in 1991. After sev-eral co-op jobs that wereentirely statistical in na-ture, he decided to pur-sue an M.Sc. in Statis-tics at Carleton Univer-sity where he receivedthe Senate Medal in 1994for his thesis work. Derekalso worked full-timeat Andersen Consulting

from 1993 to 1995. He moved out west in 1995 to pur-sue his Ph.D. studies at Simon Fraser University (SFU)under the supervision of Randy Sitter. He received hisPh.D. from the Department of Mathematics and Statis-tics at SFU in 1999, winning the Governor General’sGold Medal. After graduation he joined the Depart-ment of Statistics at the University of Michigan as anAssistant Professor. In 2003 he moved back to SFUas the Canada Research Chair (Tier II) in Industrial

Statistics in the Department of Statistics and ActuarialScience.

D. Bingham’s research interests lie in the design andanalysis of experiments in the physical and engineer-ing sciences. He has made contributions in the devel-opment of statistical methodology for the design andanalysis of experiments on complex computer simu-lators, fractional factorial designs for multi-stage ex-periments, and optimal robust parameter designs forproduct variation reduction. Much of his research hasbeen motivated through scientific collaborations. Forexample, his work on fractional factorial split-plot de-signs arose from interactions with scientists in the for-est industry. Recent work on computer experimentsand uncertainty quantification is the direct result ofcollaboration with scientists at the Los Alamos Na-tional Laboratory, the US National Center for Atmo-spheric Research, and the Center for Radiative ShockHydrodynamics at the University of Michigan. A com-mon theme in this work is the development of a frame-work for assessing the uncertainty in predictions madefrom mathematical or computer models of physicalprocesses.

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During his career, D. Bingham has published overforty papers in peer-reviewed journals and other ref-ereed contributions. His work has appeared regularlyin top-tier journals on statistics and experimental de-sign, including the Annals of Statistics, the Journal ofthe American Statistical Association, Biometrika, andTechnometrics. He co-authored a paper on variable se-lection in computer experiments that won the 2006Jack Youden Prize for best expository paper publishedin Technometrics. He has also published many papersin high-impact scientific and engineering journals fo-cusing on the application of statistical design methods.His role in the statistics community (at the Canadianand international level) is important: he is AssociateEditor for several journals and he is involved in re-search councils and SSC activities, in particular by be-ing a member of the Development Committee for theCanadian Statistical Institute.

The CRM–SSC Prize

The SSC, founded in 1977, is dedicated to the promo-tion of excellence in statistical research and practice.The prestigious CRM–SSC Prize, jointly sponsored bythe SSC and the CRM, is given each year to a Canadianstatistician in recognition of outstanding contributionsto the discipline during the recipient’s first 15 years af-ter earning a doctorate.

Derek Bingham is the fifteenth recipient of the CRM–SSC Prize. The previous winners of the award areChristian Genest (1999), Robert J. Tibshirani (2000),Colleen D. Cutler (2001), Larry A. Wasserman (2002),Charmaine B. Dean (2003), Randy Sitter (2004), JiahuaChen (2005), Jeffrey Rosenthal (2006), Richard Cook(2007), Paul Gustafson (2008), Hugh Chipman (2009),Grace Y. Yi (2010), Edward Susko (2011), and Chang-bao Wu (2012).

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The CRM Outreach Program

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The CRM Outreach Program

In 2012–2013 several public lectures geared towards a broad audience took place at the CRM. Their format wasthe same as the format of the Grandes Conférences du CRM , which feature outstanding lecturers able to convey

the beauty and power of mathematical research to a wide audience. The first two lectures below were part of aCRM program of lectures on the theme “Mathematics of Planet Earth 2013”; the third and fourth lectures were partof the Cross-Canada Series of Lectures on the same theme. The fifth lecture was part of the Grandes Conférencesseries.

In 2012–2013, the Grandes Conférences program was under the stewardship of Christiane Rousseau and YvanSaint-Aubin, professors at the Département de mathématiques et de statistique of the Université de Montréal.

Mathematics of Planet Earth 2013 — CRM Public Lectures

Mathematicians Listen as the Earth RumblesIngrid Daubechies (Duke University)by Christiane Rousseau (Université de Montréal)

Ingrid Daubechies

On April 10, 2013, In-grid Daubechies deliv-ered the fourth MPE(Mathematics of PlanetEarth) lecture in the Si-mons Lecture Series.At least 400 personsattended her lecture atthe Coeur des sciences(Université du Québecà Montréal). IngridDaubechies gave hersplendid lecture inFrench and dubbed itherself in English (in front of an empty classroom!).French and English videos are available at the sitehttp://www.videocrm.ca/.

Many people associate Mathematics of PlanetEarth 2013 with issues related to climate changeand sustainable development. The lecture by IngridDaubechies, however, fell under the first MPE theme,“A planet to discover.” In it Daubechies described hercollaboration with geophysicists and their very re-cent results concerning the formation of isolated vol-canic islands. On the floor of the oceans, the mostrecent rocks are found along the ridges where tec-tonic plates diverge. The volcanic activity along thoseridges pushes magma from the mantle upwards, andthis magma is transformed into new rocks. There ex-ist, however, isolated volcanic islands such as Hawaii,Tahiti, the Azores, Cape Verde, etc. In the Hawaiiarchipelago, the islands are aligned in order of de-creasing age, with the largest (and most recent) islandbeing the easternmost island. This observation led geo-

physicists to conjecture that these islands arose froma volcanic plume, that is, a sort of volcanic chimneythrough the mantle.

Recall that the mantle depth is approximately equal tohalf the radius of the Earth. The shifting of the sur-face tectonic plate might explain the successive for-mation of islands that are aligned, and the age differ-ences between the islands could be computed by us-ing the distances between them and the speed of thetectonic plate. Further proof is needed, however, in or-der for the scientific community to acknowledge thatthis conjecture is true. One way of proving the conjec-ture would be to “see” the plume. Remote sensing is atool for exploring the interior of the Earth: one sendssignals towards the interior and analyzes the reflectedor refracted signals on the various layers of the Earth.This technique is used when looking for oil deposits.The plumes are so far below the Earth’s crust, how-ever, that man-made signals are not powerful enoughfor conducting a remote sensing analysis. The only sig-nals that allow a detailed analysis at such depths arethe seismic waves generated by large earthquakes. In-grid Daubechies and her team had access to large databanks that contain the recordings of seismic waves (ascaptured by various stations across the globe).

Since the data are available, all that is required is agood tool for analyzing them. The problem is not triv-ial. The plumes are very thin and the perturbation ofa seismic wave speed going through a plume is of theorder of 1%. Two seismologists, Tony Dahlen and Gu-ust Noleta, contacted Ingrid Daubechies in 2005 to de-termine whether wavelets could help them solve thisproblem. Indeed, Raffaella Montelli’s promising resultshad shown that the analysis of seismic waves allowed

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one to detect perturbation zones for pressure waves (P-waves) associated with earthquakes. Such zones hadbeen identified and there was an exact correspon-dence between them and some isolated volcanic is-lands; the temperature of the ocean floor was higherin these zones. Because plumes are very thin and theperturbation of the P-waves speed is small, there isa high risk of making an error when reconstructingthe Earth’s internal structure, unless one makes use ofhigh-performance tools. In this regard wavelets are theperfect tool for analyzing local details in small regions.Moreover wavelet analysis allows one to concentrateon those small regions and disregard the other regions.

During her lecture, Ingrid Daubechies gave a mini-course on wavelet analysis as it is applied to digital im-ages. By grayscale digital image we mean a matrix ofnumbers including, for each pixel, the “gray intensity”of that pixel. This matrix is used to build four smallermatrices. The first of these contains the horizontal andvertical means of pixel pairs (where the pixels in a pairare neighbours); the second matrix contains the hor-

izontal means and vertical differences of pixel pairs;the third matrix contains the vertical means and hori-zontal differences of pixel pairs; and the fourth matrixcontains the horizontal and vertical differences of thepixel pairs. This process (i.e., the replacement of a ma-trix by four smaller matrices) is repeated on the firstmatrix. So far no information has been lost.

Ingrid Daubechies explained how wavelets allow oneto compress information and how details in a small re-gion can be extracted (in spite of the fact that much in-formation has been compressed). The use of waveletsin image reconstruction prevents errors in numeri-cal reconstruction and ensures that the singular re-gions identified within the image are indeed special.Ingrid Daubechies displayed “clean” images producedby wavelet analysis (i.e., images from which artificialregions have been removed). She was able to announce(“hot off the press”) that her collaborators and herselfhad obtained the first results for the whole Earth withreal data! The public was delighted by her lecture andasked many questions.

Königsberg’s Bridges, Holland’s Dikes, and the Fall of Wall StreetPaul Embrechts (École Polytechnique Fédérale de Lausanne)by Christian Genest and Johanna G. Nešlehová (McGill University)

Paul Embrechts

The Grandes Conférences du CRM always attract manypeople, even when they take place on a Friday night.Furthermore, on May 10, 2013, the lecture was tak-ing place within the 8th edition of the “24 heures descience”, which attracted a large audience. This audi-ence was wondering what relations existed between“Königsberg’s bridges, Holland’s dikes, and the fall ofWall Street” (the topics mentioned in the title of PaulEmbrechts’ lecture). Paul Embrechts specializes in thetheory of extreme values and quantitative risk man-agement. He has written several influential books and

more than 150 articles on these research topics. Finan-cial institutions and international regulatory bodiesfrequently ask him for advice. In his lecture he wishedto illustrate (in simple and concrete terms) the contri-bution of mathematics to the design of protective mea-sures against epidemics, floods, financial crises, andother catastrophes of this nature. The contribution ofmathematics lies in the thorough examination of riskfactors, the estimation of the probability of exceed-ing critical levels, and the study of contagion and riskpropagation in banking and social networks.

The lecture began with the famous problem of theseven bridges in the town of Königsberg: is it possi-ble to go around the city while crossing each bridgeone time and one time only? Euler proved that it is notpossible and gave a simple and general technique tosolve the problem, for any number of bridges and anybridge configuration. Euler’s solution marked the be-ginning of graph theory. In his lecture Paul Embrechtsdemonstrated the use of graph theory for modellingthe complex interdependence network between finan-cial institutions and evaluating the risk of a bankruptcybringing about the collapse of the world’s financial sys-tem (because of cross-undertakings). Basing himself on

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The CRM Outreach Program

results published in Nature in August 2012, he also ex-plained how statistical and graphical tools have beenused to evaluate the increase in the systemic risk dur-ing the mortgage loans crisis, when the risk of a singledefault triggering a domino effect was very high.

On a conceptual level, the protection of banks againstdefault risks is similar to the defense of the North Seaflat country against floods and storm tides. Nowadays,in many places, regulatory bodies demand that finan-cial institutions set aside capital reserves large enoughto offset the risk of large monetary losses. These cap-ital reserves play a role analogous to that of dikesalong the seashore. After the devastating tidal wavethat occurred in 1953, the government of the Nether-lands started building large engineering structures toprotect the shore. By taking costs and various technicalconstraints into account, the Delta Works Commissiondetermined an acceptable level of flood risk for each ofthe relevant regions. For instance, it was agreed thatin the south of Holland, dikes should be able to with-stand a flood occurring at most once every 10000 years.How can one estimate such a risk when there are nodata on the magnitude of a flood occurring once every10000 years? Paul Embrechts explained that the theoryof extreme values enables one to extrapolate beyondthe observed values. It is noteworthy that the researchcarried out in this field is due, to a large extent, to prob-abilists and statisticians who grew up in the vicinity ofthe North Sea. Paul Embrechts himself was born a fewdays after the 1953 tidal wave, very close to the affectedregion.

In finance, the bestsellers by Nassim Nicholas Talebhave popularized the phrase “black swan,” which de-notes a rare and unpredictable event having major con-sequences. Thus it should not surprise us that in fi-nance, the theory of extreme values can be used to pre-

dict and evaluate black swan events and try to avoidthem.

As they say, it never rains but it pours! Large floods oc-cur in several regions simultaneously; the movementsof the stock market often trigger the simultaneous fallof many assets; and several debtors may all of a suddenbecome unable to fulfill their engagements. When theyforget this, financial institutions underestimate theirrisk. In 2009 the media blamed the downfall of WallStreet on the “Gaussian copula”, which financial ana-lysts were using to compute the probability of multi-ple payment defaults (see for instance “The Formulathat Killed Wall Street” in the Financial Times of April24, 2009). Paul Embrechts told his audience that thiscomment by the media made as little sense as blam-ing the formula E = mc2 (due to Einstein) for thedestruction caused by atomic bombs! He also statedthat it was ironical to accuse university researchers ofhaving caused the crisis (at least indirectly), becausethey have never stopped pointing out the deficienciesof the methods used in the financial industry. As earlyas 1998, Paul Embrechts and his team had warned thatthe “Formula that Killed Wall Street” underestimated,to a considerable extent, the risk of simultaneous ex-treme events.

At the end of this fascinating lecture, many people inthe audience must have pondered the concluding re-mark by Professor Embrechts, which concerned theimportance of communication. Scientific excellenceand best practices go hand in hand thanks to a con-stant dialogue. The powerful stochastic models and in-ference techniques that are available to us will yieldtheir full potential only if their users listen to the re-searchers instead of considering them as scientists en-sconced in their ivory towers.

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Mathematics of Planet Earth 2013 — Cross-Canada Series of Lectures

The Mathematics of Light and SoundNilima Nigam (Simon Fraser University)by Jacques Hurtubise (McGill University)

Nilima Nigam

Within the framework of the MPE series organized bythe Canadian Mathematical Society and the CanadianMathematical Institutes, Professor Nilima Nigam gavea superb public lecture on February 15, 2013. In frontof a large audience, she presented and developed vari-ations on the themes of sound and light, especially fo-cusing on the description, the understanding, and theexploration of these phenomena. Nilima Nigam gave asweeping historical account of the study of light, fromthe Greeks (i.e., Empedocles) and the Romans (i.e., Lu-cretius), through the Indians of the same period (i.e.,

the school of Vaisheshika), to the 17th century (withNewton’s experiments pointing to the corpuscular na-ture of light and Huygens’ arguments in favour of thewave nature of light) and the 19th and 20th centuries(with experiments on diffraction and the photoelectriceffect that led to the wave-particle duality).

As for sound, Nilima Nigam started from the har-mony of spheres and spoke about the experiments foranalyzing the harmonics of sound, while displayingsonograms of a few simple sounds but also of JamesBrown’s voice. She analyzed for her audience the sym-metries underlying Bach’s music and explained thesuccessive refinements in our understanding of the so-lutions to wave equations. She concluded her lecturewith a very modern theme: the possibility of makingsome regions of the space impervious to sound or lightwaves by a fine-tuning of refraction indices. Althoughthis has not been achieved in the case of visible lightwaves, it has been demonstrated recently that someregions can be made impervious to micro-waves orsound waves. In summary, Nilima Nigam gave us ac-cess to a broad spectrum of science and mathematics,which bodes well for the other lectures in the series(http://cms.math.ca/Events/MPE2013/).

The mathematics of ‘fracking’Anthony Peirce (University of British Columbia)

Anthony Peirce

“Fracking” is used bythe oil and gas indus-try to enhance the pro-duction of hydrocarbons.Recently there has beenconsiderable controversysurrounding the frack-ing process due to en-vironmental concerns.Fracking makes use of aprocess called hydraulicfracturing (HF) by whichtensile fractures are in-duced to propagate in brittle materials by the injection

of a pressurized viscous fluid. In his lecture AnthonyPeirce provided examples of natural HF and situationsin which HF techniques are used in industrial prob-lems. Natural examples of HF include the formationof dykes by the intrusion of pressurized magma fromdeep chambers. They are also used in a multiplicity ofengineering applications, including: the deliberate for-mation of fracture surfaces in granite quarries; wastedisposal; remediation of contaminated soils; cave in-ducement in mining; and, as mentioned above, thefracturing of hydrocarbon bearing rocks in order toenhance productivity of oil and gas wells. Novel andemerging applications of this technology include CO2

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sequestration and the enhancement of fracture net-works to capture geothermal energy.

Anthony Peirce showed how dimensional reasoningcan be used to identify the fundamental power-lawrelationships between the variables depending on thebalance between the dominant physical processes thatare active. He described the governing equations in 1-2D as well as 2-3D models of HF, which involve a cou-pled system of degenerate nonlinear integro-partialdifferential equations as well as a free boundary. Hedemonstrated that a re-scaling of these models anddominant balance arguments can be used to identifyspecial asymptotic solutions that are of crucial impor-

tance in the location of the fracture-free boundary. Healso discussed the challenges for efficient and robustnumerical modelling of the 2-3D HF problem and sometechniques recently developed to resolve these prob-lems, including: a novel Implicit Level Set Algorithmfor solving the free boundary problem; an ExtendedFinite Element (XFEM) methodology for HF; and aKalman Filter methodology to identify the location ofpropagating fractures from remote measurements. Theefficacy of these techniques was demonstrated withnumerical results. The interested reader may consultthe site http://www.math.ubc.ca/~peirce.

Grandes Conférences du CRM

From Einstein to Wheeler: Throwing Some Light on the Wave-Particle DualityAlain Aspect (Institut d’Optique, Palaiseau)by Gilles Brassard (Université de Montréal)

Alain Aspect

On October 25,2012, the lecturehall of the Good-man Agora was fullof people enjoyinga splendid “GrandeConférence” de-livered with hu-mour and rigourby Alain Aspect,a French physi-cist who is alsoa professor at theInstitut d’Optique

(Palaiseau, France). Alain Aspect is an expert popu-ralizer of science: he apologized to his audience afterhis very first equation, saying that even people whocannot read music can appreciate a good concert. Heis considered as a potential Nobel Prize winner, onaccount of work carried out at the beginning of the1980s and demonstrating (on a distance of several me-ters) the reality of quantum intrication, a phenomenonviewed by Einstein as troublesome. Alain Aspect didnot address this topic, however, but the wave-particleduality, a phenomenon whose complete reality wasdemonstrated for the first time by himself a few yearslater. Note that Richard Feynman, renowned for hav-ing said that the wave-particle duality is the first great

mystery of quantum mechanics, changed his mindlater on and acknowledged that intrication is as mys-terious as duality. It is remarkable that Aspect’s workshed light on two mysteries!

The conference began with a history of a fascinatingquestion: what is the nature of light? More precisely, isit composed of waves or particles? From ancient Egyptand Greece, Alain Aspect led his audience to the debatebetween Huygens and Newton more than three cen-turies ago. Huygens could explain in a simple fashionthe well-known phenomena of reflection and refrac-tion while Newton argued that the chromatic decom-position of light through a prism indicated that lightwas composed of particles of various colours. New-ton’s fame ensured the adoption of his views by sci-entists, at least until the work of Young and Fresnelin 1822: it is then that the “wave” won out, because ofinterference, diffraction, and polarization phenomena,particularly the “Young’s slits” experiment. This exper-iment consists of letting a beam of light go throughtwo slits and observing so-called interference bands,i.e., bands that are alternatively bright and dark, ona screen behind the slits. Around thirty years later,Maxwell determined that light waves were actuallyelectromagnetic waves. Everything seemed so clear atthat point that one could be forgiven for thinking, atthe end of the XIXth century, that the study of the-oretical physics was complete. Lord Kelvin, however,

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pointed out that two unexplained “clouds” remained,and these clouds gave rise to the two great revolutionsin XXth century physics: relativity and quantum me-chanics. Alain Aspect stated boldly that the latter wasthe most extraordinary theory ever devised by the hu-man species.

In 1905 Einstein had the audacity of proposing a “par-ticle” theory of light in order to explain the photo-electric effect. This heretical theory was not immedi-ately accepted and Millikan tried to show that is wasfalse through experiments, but these experiments ac-tually corroborated Einstein’s theory in 1915 and Ein-stein won the Nobel Prize for Physics in 1922. How canone reconcile this “particle definition” of light with thediffraction, interference, and polarization experimentsby Young and Fresnel? Is light a wave or does it consistof particles? Einstein answered this question in 1909 byputting forward the wave-particle duality, which wasat the heart of Alain Aspect’s lecture. This theory pos-tulates that light is composed of indivisible particles(which have been called “photons” since 1926), but thateach photon can behave like a wave and in particularinterfere with itself when going through two slits. Howcan we know whether this is a good model of light?

In the 1950s Feynman imagined a thought experimentwith a purely pedagogical goal. If one could redo theYoung slits’ experiment by sending one photon at atime towards the slits, then one could exclude theclassical theory, according to which a photon goingthrough one of the slits interferes with another photongoing through the other slit. Feynman was not suggest-ing to carry out this experiment since nobody was ableto manipulate individual photons at the time! It is easy,however, to emit a light beam containing a number ofphotons following a Poisson law whose intensity canbe chosen a priori. This seems to entail the feasibilityof an experiment with a beam so thin that the pho-tons would go through the slits one by one, like thedrops of a faucet that leaks very slowly. Unfortunatelythis would not correspond to Feynman’s experiment,since the Poisson law still allows for the possibility ofseveral photons within a very short interval. Indeed,a mathematical computation shows that a purely cla-sical theory, in which no photon goes through morethan one slit, accounts in an exact fashion for the in-terference phenomena that would be observed in suchan experiment!

Therefore, if one wishes to realize Feynman’s experi-ment in practice, one must get hold of a source of iso-

lated photons (also called “unique photons”). This ex-periment was finally carried out in 1985 by Alain As-pect and his first doctoral student, Philippe Grangier.How does one produce unique photons? With a dead-pan sense of humour, Alain Aspect began his expla-nation by giving us a so-called “kitchen recipe”. Whilegoing from an excited state to its ground state, an atomproduces one and only one photon. Thus to produce aunique photon, it suffices to take a single atom, to “ex-cite” it, and to wait! Unfortunately no one knew howto isolate an atom in 1985. In looking for a methodof producing unique photons, Alain Aspect took hisinspiration from the montage that had allowed himto prove the existence of intrication a few years be-fore. One designs an assembly of atoms emitting mil-lions of photons every second, but these photons areemitted in pairs of different colours. Each emission ofa green photon (551 nm) is followed, a few nanosec-onds later, by the emission of a violet photon (423 nm).Hence one only has to detect green photons to knowwhether they are the “harbingers”, with a high proba-bility, of the emission of a unique violet photon. At thetime this montage required a cumbersome equipmentwhose manipulation was akin to an art. Alain Aspectcould not refrain from mentioning that this experimentcan be carried out nowadays in a “disgustingly simple”fashion!

Alain Aspect and Philippe Grangier were at last ableto realize the thought experiment proposed by RichardFeynman and to observe (naturally) the results pre-dicted by quantum mechanics. Thus it took more than75 years to verify the theory of wave-particle dualityfirst stated by Einstein in 1909! But neither the storynor the lecture ended with this achievement: on thecontrary, things became even more fascinating.

When our photon comes across a beam splitter, will itbehave like a wave and follow the two paths simulta-neously (like the photon of Young’s experiment, whichgoes through the two slits at the same time) or like aparticle and follow one of the two paths? It seems thatthis “decision” depends upon what will be “required” ofthe photon later on! If the two potential paths are re-combined, then an interference phenomenon will oc-cur, which suggests a “wave-like” behaviour. On theother hand, if one attemps to detect the two paths inde-pendently, only one of the “detections” will be success-ful, which suggests a “particle-like” behaviour. Doesthe photon that comes across a beam splitter have to“open out its antennas” (this is my phrase) in order to

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choose a behaviour depending upon the continuationof its path? In 1978 John Archibald Wheeler proposeda thought experiment called “delayed choice”, in whichthe continuation of the photon path is chosen ran-domly just after the photon has gone through the beamsplitter. By now you must have guessed that Alain As-pect did also carry out this experiment (in 2007) andthat quantum mechanics triumphed one more time!Note that other researchers had carried out this exper-iment before him, but not with a source of unique pho-tons; hence their experiments did not prove anything.Alain Aspect concluded this section of his lecture bystating that “the delayed choice experiment is hard onthe photon!” Being modest (as always), he added thathis experiment had succeeded because “we had verygood students.” Let us mention particularly VincentJacques, the first doctoral student of Jean-François Roy,himself the first doctoral student of Philippe Rangier(Alain Aspect’s first doctoral student, as you may re-call). It is a great family history!

How is all of this possible? Alain Aspect suggested that“when one does not understand anything any more,one goes back to Niels Bohr” and added (with a smile)that Bohr’s writings are “like those of Nostradamus.”Indeed they are often very obscure. Aspect provokedthe laughter of the audience by stating that in Bohr’sexplanations, one finds not only the wave-particle du-ality but the complementarity between accuracy andclarity. He also said that “with geniuses, one is allowedto make jokes!”

Aspect concluded his lecture by outlining the conceptunderlying quantum cryptography, which he calls a“true revolution” (thank you!) and proves that ask-ing fundamental questions may lead to practical ap-plications. Allow me to add: “Long live fundamentalresearch!” Our unforgettable lecturer gave us a lastpresent, a family snapshot depicting four generationsof researchers: Vincent Jacques, Jean-François Roch,Philippe Grangier, and of course Alain Aspect himself.This magical night ended with thunderous applause.

Thank you Alain for your generosity!

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The CRM is strongly committed to its national mission and takes measures to ensure that as many Canadianscientists as possible benefit from its activities and become involved in their planning. For instance, it ap-

points to its International Scientific Advisory Committee eminent Canadian scientists from various parts of thecountry; it is present in all important forums where the future directions of the Canadian mathematical sciencesare discussed; it urges its organizers to ensure that Canadian specialists are included in their activities; it organizesand supports scientific events across the country; it collaborates with Canadian institutes, societies, and associa-tions. A specific budget is set aside each year for the participation of Canadian graduate students in its programs.The CRM is the only national institute that operates in the two official languages of Canada and it is highly visibleon the international scene. In keeping with its national role, it coordinates its activities with the Fields Institutefor Research in Mathematical Sciences, the Pacific Institute for the Mathematical Sciences (PIMS), the Mprimenetwork, the Canadian Mathematical Society (CMS), the Canadian Applied and Industrial Mathematics Society(CAIMS), the Statistical Society of Canada (SSC), the Canadian Association of Physicists (CAP), as well as othersocieties and institutes abroad.

CRM Partners

The Fields Institute for Research inMathematical Sciences and the PacificInstitute for the Mathematical Sciences

Since the early 1990s two other research instituteshave joined the CRM on the Canadian scene: Toronto’sFields Institute for Research in Mathematical Sciencesand the Pacific Institute for the Mathematical Sciences(PIMS). As well as coordinating their scientific activi-ties, the three institutes have worked closely on a va-riety of initiatives, the most important of which is theMprime network. The three institutes are also involvedin other initiatives, such as the CRM–Fields–PIMSPrize awarded in recognition of outstanding accom-plishments in the mathematical sciences in Canada. Itwas created in 1994 as the CRM–Fields Prize and be-came the CRM–Fields–PIMS Prize in 2006. The admin-istrative responsibility for this prize rotates betweenthe three institutes.

National and International Collaborations

The CRM collaborates with research centres in theMontréal area, especially the Groupe d’études et de re-cherche en analyse des décisions (GERAD). The CRM,the ISM, and GERAD jointly organize a weekly statis-tics colloquium (see the section General Program). TheCRM is a partner of the Banff International ResearchStation (BIRS).

The researchers belonging to the CRM or a CRM lab-oratory enjoy close collaborations with French col-leagues, in particular CNRS and INRIA researchers.In 2011 an Unité Mixte Internationale (UMI) of theCNRS was established at the CRM. This UMI sup-

ports visits of French mathematicians to members ofthe CRM and vice versa. In 2012-2013 the followingFrench mathematicians visited the CRM: Marie Al-benque (CNRS, Palaiseau), Mattia Cafasso (Angers),Pierre Conte (CEA/Saclay), Virgile Ducet (Ph.D. stu-dent in Marseille), Gérard Freixas i Montplet (CNRS,Paris), Emmanuel Fricain (Lille), Carlo Gasbarri (Stras-bourg), Paolo Ghiggini (CNRS, Nantes), Pierre Ille(CNRS, Marseille), Muath Karaki (Ph.D. student inLille and Lyon), Annalisa Panati (Toulon), Vincent Pi-laud (CNRS, Palaiseau), Claude-Alain Pillet (Toulon),Jean-Philippe Préaux (Marseille), Erwan Rousseau(Marseille), and Sheila Sandon (CNRS, Strasbourg).Three Montréal researchers (Louigi Addario-Berry,from McGill, Laurent Habsieger, the UMI director,and Geña Hahn, from the Université de Montréal)visited colleagues in France thanks to the UMI. Formore information we refer the reader to the sitewww.crm.umontreal.ca/UMI/. In 2012-2013 the rela-tionship between the CRM and French researchers alsoresulted in the organization of two colloquia within theEntretiens Jacques-Cartier: a colloquium on risk man-agement and a colloquium on mathematical physics.We refer the reader to the section on the CRM generalprogram for reports on these colloquia.

The CRM has signed agreements with the EuropeanUnion. For instance, in 2006 the CRM and the ISMsigned an agreement with the ALGANT consortium(where ALGANT stands for Algebra, Geometry, Num-ber Theory) to further the exchange of graduate stu-dents. In 2010 the CRM was one of the 12 partnersto sign an agreement with SISSA (an Italian centre) topromote exchanges of visiting researchers specializing

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in mathematical physics. SISSA (International Schoolfor Advanced Studies, in English) is based in Triesteand is a university dedicated to the training of grad-uate students. In December 2012 the CRM signed anagreement with the Institute of Mathematics and Com-puter Science of the Academy of Sciences of Moldova.The purpose of this agreement is to exchange profes-sors for lectures and research projects, to conduct jointresearch projects, and to support joint supervision andtutoring of Ph.D. students.

The CRM has signed two agreements with the Tata In-stitute of Fundamental Research (TIFR), a prestigiousresearch centre in India. The scope of the first agree-ment was applied mathematics and it was signed in2006 between the CRM and the TIFR Centre for Appli-cable Mathematics in Bangalore. The scope of the sec-ond agreement was pure mathematics and was signedin 2011 between the CRM and the Mumbai TIFR.

In its publishing activities, the CRM is continuing itspartnership with the American Mathematical Society(AMS), in particular through its two series of joint pub-lications, the CRM Monograph Series and the CRMProceedings & Lecture Notes. A CRM Series in Mathe-matical Physics is published by Springer. The CRM hasexchange agreements with the Fields Institute for Re-search in Mathematical Sciences, PIMS, the MSRI, theInstitute for Mathematics and its Applications (Uni-versity of Minnesota), the École normale supérieure(France), the Isaac Newton Institute, the Institut desHautes Études Scientifiques (France), and BIRS.

Associations and Professional Societies

The CRM maintains close ties with the different pro-fessional societies in the mathematical sciences: CMS,CAIMS, SSC, and CAP. The president of the CMS is anex-officio member of the International Scientific Advi-sory Committee of the CRM. The CRM has also sup-ported financially certain initiatives of the CMS, suchas the mathematical camps. Together with the otherinstitutes, the CRM organizes or sponsors special ses-sions at the CMS, CAIMS, and SSC meetings. The CRMawards a prize each year jointly with the SSC; simi-larly, it awards a prize each year with the CAP in math-ematical and theoretical physics.

The Mprime Network

The Mprime network (www.mprime.ca) is the onlyNetwork of Centres of Excellence for the mathemat-

ical sciences, bringing together academia, industry,and the public sector to develop cutting edge mathe-matical tools vital to our knowledge-based economy.Known as Mitacs (Mathematics of Information Tech-nology and Complex Systems) from 1999 to 2011, itis a pan-Canadian network whose creation was pro-posed by the three Canadian mathematical sciences in-stitutes (the CRM, the Fields Institute for Research inMathematical Sciences, and PIMS). The organizationnow called Mathematics of Information Technologyand Complex Systems is not focused solely on math-ematics but on the development of the next generationof innovators with vital scientific and business skills(see www.mitacs.ca).

The purpose of the Mprime network (formerly knownas Mathematics of Information Technology and Com-plex Systems) was to lead Canada’s effort in the gen-eration, application, and commercialization of newmathematical tools and methodologies within a world-class research program. In order to do so, Mprime initi-ated and fostered linkages with industrial, governmen-tal, and not-for-profit organizations. Mprime researchfocuses on five key sectors of the economy: biomedicaland health sector; environment and natural resources;information processing; risk and finance; and commu-nication, networks, and security.

Atlantic Association for Research in theMathematical Sciences (AARMS)

AARMS was founded in March 1996 at a time whenthe National Network for Research in the Mathemati-cal Sciences was being discussed and planned. AARMSexists to encourage and advance research in all mathe-matical sciences (including statistics and computer sci-ence) in the Atlantic region. In addition AARMS acts asa regional voice in discussions of the mathematical sci-ences on a national level. Since its inception, AARMShas played an important role in the research activitiesin the Atlantic region, sponsoring or co-sponsoringnumerous meetings and workshops. In the summerof 2002, AARMS initiated an annual Summer Schoolfor graduate students and promising undergraduates.AARMS is grateful to Canada’s three mathematical in-stitutes (the CRM, the Fields Institute for Research inMathematical Sciences, and PIMS), as well as to themember universities, for providing funding for its ac-tivities. Its member universities are Acadia University,Cape Breton University, Dalhousie University, Memo-rial University of Newfoundland, Mount Allison Uni-

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versity, St. Francis Xavier University, Saint Mary’sUniversity, the Université de Moncton, the Universityof New Brunswick, and the University of Prince Ed-ward Island. Finally AARMS receives some financialsupport from the provinces of New Brunswick andNova Scotia. One can find information on the activi-ties of AARMS at the following web site: http://www.aarms.math.ca.

Academic Partners

The activities of the CRM rest on a solid basis of co-operation with regional universities, in particular theMontréal universities, and most particularly the Uni-versité de Montréal, whose support for the CRM hasbeen unfailing. The Université de Montréal releasesfive of its faculty members to work at the CRM eachyear, and the support of these faculty members is anessential asset for the scientific activities of the CRM.There is in addition a regular program of teaching re-leases for the other Montréal universities, bringing theequivalent of another two positions to the CRM eachyear. On an ad-hoc basis linked to the thematic pro-gram, the CRM has also been arranging the release ofresearch personnel from nearby universities such asLaval, Sherbrooke, Queen’s, and Ottawa. The partner-ships of the CRM with the other research institutes inthe Montréal area have been very profitable.

With the financial support of the Université de Mont-réal, McGill University, the Université du Québec àMontréal, Concordia University, and Université Laval,as well as grants from NSERC and the Fonds de re-cherche du Québec – Nature et technologies (FRQNT),the CRM finances the activities of its nine laboratories,which collectively represent the most active branchesof the mathematical sciences. These laboratories arethe perfect illustration of scientific vitality and serve tofeed the national and international scientific programsof the CRM. The reader may refer to the section Re-search Laboratories for a description of the activitiesof each of these laboratories.

Association with the University of Ottawa

In 2003, the Department of Mathematics and Statisticsof the University of Ottawa became a member of theCRM. In partnership with the University of Ottawa,the CRM cofinances the CRM–University of OttawaDistinguished Lecture Series, postdoctoral fellowships,

and teaching releases so that University of Ottawa fac-ulty members can undertake research with colleaguesin the laboratories of the CRM or participate in the sci-entific activities of the CRM.

CRM–University of Ottawa DistinguishedLecture Series

The series features talks by prominent mathematiciansfrom Canada and abroad on topics at the forefrontof today’s mathematical research. In 2012–2013 therewere two such talks at the University of Ottawa.

Free probability and random matrices, by Alice Guion-net (MIT), on March 1st, 2013

Familles d’algèbres de quaternions et d’octonions, byPhilippe Gille (École Normale Supérieure, Paris), onApril 5, 2013

Network for Computing and MathematicalModeling (ncm₂)

The CRM is one of the founding members of theNetwork for Computing and Mathematical Modeling(ncm₂), a network created by several research cen-tres in order to respond to the needs of industry infields related to computing and mathematical mod-elling. The research of the network focuses on fivemajor themes: risk management, information process-ing, imaging and parallel computing, transport andtelecommunications, and health and electronic com-merce. The ncm₂ was founded by the CRM, the Centrede recherche en calcul appliqué (CERCA), the Cen-ter for Interuniversity Research and Analysis on Or-ganizations (CIRANO), the Centre for Research onTransportation (CRT), the Computer Research Insti-tute of Montréal (CRIM), and the Institut national de larecherche scientifique – Télécommunications (INRS-Télécom). At the present time the following centres aremembers of the ncm₂: CIRANO, CRM, CIRRELT, INRS-ÉMT, and GERAD.

Regroupement Neuroimagerie/Québec(RNQ)

In recent years, the PhysNum laboratory of the CRMhas developed a strong collaborative network with var-ious partners in neuroimaging in the Montréal area.This network became an officially recognized networkwith the founding of the Regroupement Neuroima-gerie/Québec (RNQ), under the umbrella of the Insti-

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tut universitaire de gériatrie de Montréal. One of thestrongest alliances of the CRM within that networkis its association with the Inserm laboratory for brain

imaging at FMPMC Pitié-La Salpêtrière (Paris), whosedirector is Dr. Habib Benali.

Joint Initiatives

The annual meetings of the CMS, SSC, and CAIMS, aswell as some of their training and promotion activi-ties, are jointly sponsored by the CRM, the Fields In-stitute for Research in Mathematical Sciences, PIMS,and Mprime. The annual meetings of the societiesallow Canadian mathematicians and statisticians tokeep abreast of their colleagues’ work, to organize ses-sions on emerging topics, and attend lectures givenby world-renowned mathematicians or prize winners.One can find more information on the societies by con-sulting their respective web sites (http://www.cms.math.ca/, http://www.ssc.ca/, and http://www.

caims.ca/). Note that the CRM was the host of the2012 CMS Winter Meeting, which took place at theFairmont Queen Elizabeth Hotel in Montréal.

2012 CMS Summer MeetingJune 2–4, 2012, Reginahttp://cms.math.ca/Events/summer12/

40th Annual Meeting of the Statistical Society ofCanadaJune 3–6, 2012, Guelphhttp://www.ssc.ca/en/meetings/2012/

Canadian Applied and Industrial Mathematics AnnualMeeting, CAIMS 2012June 24–28, 2012, the Fields Institute for Research inMathematical Scienceshttp://www.fields.utoronto.ca/programs/

scientific/11-12/CAIMS_SCMAI/

2012 CMS Winter MeetingDecember 7–10, 2012, Fairmont Queen Elizabeth,Montréalhttp://cms.math.ca/Events/winter12/

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Mathematical Education

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Centre de recherches mathématiqes

As part of its mandate to promote and stimulate research in the mathematical sciences, at every level, the CRMprovides funding and support for many activities and programs related to mathematical education and the

training of researchers. Many of these activities and programs are carried out jointly with the ISM (Institut dessciences mathématiques). As a result, much of the information contained in the present section is taken from theISM annual report.

Institut des sciences mathématiques (ISM)

Created in 1991 by the departments of mathemat-ics and statistics of the four Montréal universities,the ISM is a consortium of eight Québec universities(Bishop’s University, Concordia, Laval, McGill, Uni-versité de Montréal, UQAM, UQTR, and Université deSherbrooke), six of which offer a Ph.D. program inMathematics. As an institute to which belong almostall the Québec researchers in the mathematical sci-ences, the ISM has at its disposal vast material andintellectual resources, and as a result, Montréal andQuébec itself have become one of the main centres oftraining and research in the mathematical sciences inNorth America. The ISM is funded by the Ministère del’Éducation, du Loisir et du Sport du Québec and by theeight universities in the consortium.

The reader will find below an overview of the activitiesand programs of the ISM.

• Coordination and harmonization of graduate pro-grams

The ISM was created to bring together the strengthsof its member departments, in order to turn them intoa great school of mathematics. Thus the ISM coordi-nates the graduate studies of the mathematics depart-ments, supports the sharing of expertise among its re-searchers, and facilitates student mobility between theMontréal universities.• Scholarships and financial supportThe ISM helps students and beginning researcherscarry out their research activities in several ways, forinstance through the ISM Scholarships for GraduateStudies, the Carl Herz Scholarship (financed by theCarl Herz Foundation), the Travel Bursaries, the Un-dergraduate Summer Scholarships, and the CRM–ISMpostdoctoral fellowships.• Scientific activitiesSince its creation, the ISM has initiated several activ-ities that are by now an integral part of the Québecscientific scene: the CRM–ISM Mathematics Collo-quium, the CRM–ISM–GERAD Statistics Colloquium,

the CRM–ISM Probability Seminar, and the ISM Grad-uate Student Conference.• Promotion of the mathematical sciencesThe ISM produces the Accromαth journal and dis-tributes it freely in all the cégeps and secondaryschools in Québec. In this way, it contributes to spread-ing mathematical knowledge among teachers, youngstudents, and the general public. Each year, ISM pro-fessors give talks attended by thousands of cégep stu-dents; these talks present the latest breakthroughs inmathematics and the careers available to mathematicsgraduates.

As the above list demonstrates, the CRM has severaljoint activities with the ISM, in particular two collo-quia, a joint program of postdoctoral fellowships, andthe planning of graduate courses related to the the-matic programs of the CRM. Since the summer of 2003,the CRM has also supported the Undergraduate Sum-mer Scholarships program, which allows postdoctoralfellows to supervise undergraduate students doing re-search.

CRM–ISM Postdoctoral Fellowships

The CRM–ISM postdoctoral fellowships enablepromising young researchers to devote themselves totheir research work. The ISM organizes a single com-petition on behalf of the eight universities of the con-sortium, and it receives a large number of applications,which are then evaluated by the 150 ISM professors.The selection of the fellows is rigorous and only one inforty applicants is awarded a fellowship. The applica-tions are handled electronically in order to streamlinethe selection process and economize the resources con-sumed during the selection. The postdoctoral fellowsplay a crucial role in the Montréal universities: theycollaborate with the established researchers, stimulatetheir work, and bring new ideas from other great cen-tres of mathematical research. Also they are a vitallink between the professors and the students, espe-

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cially when they organize on their own study groupson emerging topics.

CRM–ISM 2012–2013 Postdoctoral Fellows

Jessica Banks (Ph.D., Oxford) works with StevenBoyer in the field of low-dimensional topology, espe-cially knot theory.

Vorrapan Chandee (Ph.D., Stanford) works withChantal David and Andrew Granville on analytic andprobabilistic number theory, L-functions, the theoryof random matrices, and quadratic forms.

Adam Harper (Ph.D., Cambridge) works with An-drew Granville in analytic number theory.

Dmitry Kolomenskiy (Ph.D., Université de Pro-vence) works in applied mathematics with RobertOwens and Jean-Christophe Nave.

Antonio Lei (Ph.D., Cambridge) works with HenriDarmon in algebraic number theory.

Alejandro Morales (Ph.D., MIT) works with Fran-çois Bergeron in algebraic and enumerative combina-torics.

Yakov Savelyev (Ph.D., Stony Brook) works with Oc-tav Cornea and François Lalonde in symplectic and dif-ferential geometry. His main interests are Floer theoryand Gromov-Witten theory in dynamical systems andmathematical physics.

Undergraduate Summer Scholarships

In collaboration with the CRM and the ISM professors,the ISM awards summer scholarships to promising un-dergraduates who want to do research during the sum-mer and plan to study mathematics at the graduatelevel. These undergraduates are supervised by postdoc-toral fellows, who in general are supervising studentsfor the first time. The reader will find below the list ofthe undergraduate scholars for the summer of 2013.

Alex De Serre Rothney (Bishop’s)Scholarship co-financed by Trevor Jones and BradWillmsSupervisors : Trevor Jones and Brad WillmsTopic : Symmetric Toeplitz MatrixDuration : May 1 – August 31 (4 months)

Nicholas Galbraith (McGill)Scholarship co-financed by Steven BoyerSupervisor : Jessica BanksTopic : Physical Knot TheoryDuration : May 1 – July 15 (2,5 months)

Olivier Gingras (Montréal)Scholarship co-financed by Pavel WinternitzSupervisor : Danilo RiglioniTopic : Superintegrable systemsDuration : May 1 – August 31 (3.5 months)

Samuel Laferrière (McGill)Scholarship co-financed by Frédéric RochonSupervisor : Carl TiplerTopic : Riemann-Roch theorem on singular surfacesDuration : May 1 – July 31 (3 months)

Thomas Ng (McGill)Scholarship co-financed by Dmitry JakobsonSupervisor : Suresh EswarathasanTopic : Spectrum and eigenfunctions of Laplacian oncompact, finite area and infinite area hyperbolic sur-facesDuration : May 1 – July 31 (3 months)

Manuela Pineros-Rodriguez (Montréal)Scholarship co-financed by Dimitris KoukoulopoulosSupervisor : Mariah HamelTopic : Encryption, factorization, and primality testingalgorithmsDuration : May 1 – August 31 (4 months)

William Wright (McGill)Scholarship co-financed by Henri DarmonSupervisor : Miljan BrakocevicTopic : Rational points on modular elliptic curvesDuration : May 1 – August 31 (4 months)

Dongliang Zhang (McGill)Scholarship co-financed by David StephensSupervisor : Will AstleTopic : Model selection in complex settingsDuration : May 1–August 31 (4 months)

ISM Graduate Student Conference

Each year the ISM sponsors and supports the organi-zation of the ISM Graduate Student Conference (“Col-loque pan-québécois des étudiants de l’ISM”). Orga-nized by and for the students of the partner univer-sities, the 14th Conference was held on May 17–19,2013, at McGill University. It was organized by HadiBigdely, Kael Dixon, Olivier Mercier, and Juan Igna-cio Restrepo and attended by around 80 participants.The program featured five plenary lectures and presen-tations by students. The plenary lectures were givenby Marc Lackenby from the University of Oxford (Rei-dmeister moves for the unknot), Robert Pollack from

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Boston University (Congruences and families of modu-lar forms), David Wolfson from McGill University (TheStatistical analysis of survival data : A personal journey),Yves Bourgault from the University of Ottawa (Modèleset calculs en électrophysiologie cardiaque), and Moham-mad Najafi Ivaki from Concordia University (Centro-affine normal flows). Note that Mr. Ivaki was awardedthe Carl-Herz Prize for 2013.

The following students gave talks during the Confer-ence: Adam Alcolado (McGill), Jean Auger (Laval), Mo-hammad Bardestani (Montréal), Léo Belzile (McGill),Yara Elias (McGill), Marc Éthier (Sherbrooke), An-drew Fiori (McGill), Alexandre Foucault (Mont-réal), Patrick Letendre (Laval), Maryam Lotfipour(Montréal), Thierry Moisan (Laval), Leta Montopoli(McGill), Sébastien Picard (McGill), Emilie Picard-Cantin (Laval), Benoît Pouliot (Laval), Ben Smith(McGill), Mashbat Suzuki (McGill) et Jean-SébastienTurcotte (Montréal).

Promotion of the Mathematical Sciences

Produced by the ISM and financed by the ISM, theCRM, the CMS, and the Mprime network, the Ac-

cromαth magazine aims to draw more young people tothe mathematical sciences. Accromαth, whose editor-in-chief is André Ross, has two issues per year andis available free of charge in all the high schools andcégeps of Québec. Accromαth is designed by an ex-ceptional team of researchers and instructors with abroad experience in the promotion of mathematics; itprovides high school and cégep teachers with stimulat-ing and topical articles on the most recent discoveriesand applications, as well as articles on the history ofmathematics and its links with the arts.

The last year was particularly fruitful for Accromαth.The Spring 2013 issue was devoted to the Mathemat-ics of Planet Earth, so as to be included in the world-wide year on the same theme. More than 8000 copiesof that issue were printed, thanks to the extraordi-nary support of the Canadian Mathematical Society($1200) and the FRQNT ($2000). Copies of the specialissue were also printed and distributed in 14 French-speaking African countries, thanks to the support ofthe Canadian Commission for Unesco ($3000), the In-ternational Commission on Mathematical Instruction($1000 US), UNESCO ($2000), and the InternationalMathematical Union (€2000).

Other Joint Initiatives

56e Congrès de l’Association MathématiqueduQuébecOctober 12–13, 2012, Cégep de Sainte-Foy

As usual the CRM was a sponsor of the “AssociationMathématique du Québec” conference, which tookplace at the Cégep de Sainte-Foy and whose themewas Les mathématiques ludiques (Recreational mathe-matics).

“Sciences et mathématiques en action” and“Association québécoise des jeuxmathématiques”

The CRM contributes to the “Sciences et mathéma-tiques en action” program, created by Professor Jean-Marie De Koninck from Université Laval in order topopularize mathematics and science for high schoolstudents and the general public. We refer the readerto the site www.smac.ulaval.ca for more information.The CRM also supports the Association québécoise desjeux mathématiques (aqjm.fsg.ulaval.ca).

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Research Laboratories

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Centre de recherches mathématiqes

In 2012–2013 the CRM was encompassing nine research laboratories at the heart of the Québec mathematicalcommunity. These research groups act as focal points for local scientific activity and participate actively in the

scientific programs of the CRM.

Applied Mathematics

Description

The Applied Mathematics Laboratory is a research net-work of 23 applied mathematicians, engineers, com-puter scientists, and chemists, based in Montréal. TheLaboratory exists primarily to stimulate research andcollaboration in the applied mathematical research ar-eas of its members by fostering discussion and the cre-ation of ideas through conferences, workshops, andseminars, and the furtherance of research throughits visitors’ program and the appointment of talentedpostdoctoral fellows. The Laboratory is also very con-cerned with the training of young researchers and sup-ports travel and conference attendance of its postdoc-toral fellows.

The research interests of the Laboratory members arequite diverse although there are a number of com-mon threads that make interchange and collaborationboth possible and fruitful. Active areas of researchrepresented within the Laboratory include, for exam-ple, the application of dynamical systems theory tocomplex phenomena, high-dimensional chaos, and bi-ology. There is an interest in numerical linear alge-bra and its applications, including the design, analysis,and implementation of effective computer algorithms.Amongst the membership one will also find expertisein numerical simulation, applied dynamical systems,quantum chemistry, turbulence, combustion, biome-chanics, numerical methods in fluid mechanics andelectromagnetism, hp-finite element methods, molec-ular dynamics, control, optimization, preconditioners,and large-scale eigenvalue problems.

News and highlights

The Applied Mathematics Laboratory has strengths intraditional areas of continuous applied mathematics(notably partial differential equations, applied analy-sis, and numerical methods), but discrete mathemat-ics and optimization are increasingly important in ap-plications. From now on these topics will be well rep-resented in the Laboratory, because two McGill pro-fessors working in discrete mathematics have joined

the Laboratory: Adrian Vetta (algorithmic game the-ory) and Bruce Shepherd (combinatorial optimizationand graph theory). In the 2012–2013 academic year 17M.Sc. students, 27 Ph.D. students, and 15 postdoctoralfellows were supervised or cosupervised by membersof the Applied Mathematics Laboratory. About 10 ofthese students and PDFs graduated in 2012–2013 andthey have moved on to positions in industry (Ora-cle, Nuance) and academia (Texas at Austin, Grenoble,Montréal, INRS).

Members of the Laboratory

Regular members

Robert G. Owens (Montréal), Director (until January8th, 2013)Mechanics, numerical simulation of complex fluidsAdam M. Oberman (McGill), Director (from January8th, 2013)Numerical solution and analysis of nonlinear ellipticpartial differential equationsAndré D. Bandrauk (Sherbrooke)Quantum chemistryPeter Bartello (McGill)Turbulence, CFDJacques Bélair (Montréal)Dynamical systems in physiology

Anne Bourlioux (Montréal)Modelling, numerical simulation in turbulent combus-tion

Xiao-Wen Chang (McGill)Numerical linear algebra and applications

Rustum Choksi (McGill)Calculus of variations, nonlinear partial differentialequations, problems arising in materials science, self-assembly of diblock copolymers and magnetic domainformation in type-1 superconductors and ferromag-netsEusebius J. Doedel (Concordia)Numerical analysis, dynamical systems, differentialequations, bifurcation theory, scientific software

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Eliot Fried (McGill)Mechanics and thermodynamics of continuous mediaGeorge Haller (McGill)Theory of nonlinear dynamical systems, fluid mechan-ics, Hamiltonian systems, singular perturbation theoryAntony R. Humphries (McGill)Numerical analysis, differential equationsEmmanuel Lorin de la Grandmaison (Carleton)Numerical analysis for hyperbolic systems, quantumchemistry, complex applications of finite volumes,computer scienceSherwin A. Maslowe (McGill)Asymptotic methods, fluid mechanicsJean-Christophe Nave (McGill)Numerical analysis, PDE, interface problems, level setmethods, fluid mechanics, computer graphicsGantumur Tsogtgerel (McGill)Applied mathematics, partial differential equations,general relativityJian-Jun Xu (McGill)Asymptotics and numerical analysis, nonlinear PDEs,materials science

Associate members

Tucker Carrington (Queen’s)Chemical dynamics

Martin J. Gander (Genève)Domain decomposition, preconditioningJean-Philippe Lessard (Laval)Dynamical systems, rigourous computational meth-ods, PDEs, delay differential equations, topologicalmethodsNilima Nigam (Simon Fraser)Applied analysis, numerical methods in electromag-netismPaul F. Tupper (Simon Fraser)Numerical analysis, stochastic processes, statisticalmechanicsThomas P. Wihler (Bern)Numerical analysis, computational methods for PDEsJean-Paul Zolésio (INRIA Sophia Antipolis)Control, optimization

CICMA — Centre Interuniversitaire en Calcul Mathématique Algébrique

Description

CICMA brings together researchers working in num-ber theory, geometric group theory, and algebraicgeometry. Algebraic geometry is a broad disciplinewith strong connections to a variety of areas rangingfrom arithmetic to theoretical physics. Eyal Goren andAdrian Iovita are leading experts in applying algebro-geometric techniques to problems motivated by num-ber theory, notably the study of Shimura varieties andp-adic cohomology theories. John McKay is one of theinstigators of the moonshine program, which ties to-gether in a surprising way certain notions in the theoryof modular forms, arithmetic geometry, and theoreti-cal physics. Geometric group theory is a vibrant sub-ject that has melded geometric and algebraic methodsin deep and powerful ways, leading to novel insights inboth subjects. Dani Wise and Mikaël Pichot are world-renowned specialists in this central area.

Contemporary algebraic number theory has developedover the last decades following two major trends. Onone hand, there is the theory of special values of L-functions attached to arithmetic objects, originating in

the work of Gauss and Dirichlet and leading to themodern conjectures of Deligne, Beilinson, and Bloch–Kato. On the other hand, the Langlands program pos-tulates a close link between arithmeticL-functions andautomorphic representations. Analytic number theorystudies profound and subtle questions about the distri-bution of prime numbers, using powerful techniquesfrom analysis, notably the theory of functions of acomplex variable and spectral theory. Number theoryin all its different flavours is particularly well repre-sented in the laboratory, with Darmon, Goren, Iovita,and Kassaei on the arithmetic and automorphic side,and David, Granville, Kisilevsky, Koukoulopoulos, andLalín on the more analytic side of the subject.

News and highlights

CICMA is well known internationally for attractingtop quality students and PDFs from around the world.Each year the Laboratory organizes a dazzling arrayof activities that foster the exchange of ideas betweenstudents and researchers, from Montréal and the restof the world: (a) the Québec-Vermont Number The-ory Seminar (which has become the most important

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forum in Canada for the presentation of the latest de-velopments in number theory); (b) the Québec- MaineConference; (c) the Montreal-Toronto Workshops inNumber Theory; (d) the Bellairs Workshop in Num-ber Theory (the topic of the May 2013 workshop was“Arithmetic intersection theory on Shimura varietiesand derivatives of L- functions”); (e) the SHAPE (Sémi-naire Henri-Adrian-Payman-Eyal); and (f) The Ana-lytic Number Theory Seminar. In the 2012–2013 aca-demic year 5 undergraduate students, 28 M.Sc. stu-dents, 42 Ph.D. students, and 16 postdoctoral fellowswere supervised or cosupervised by CICMA members.

Regular members of the Laboratory

Henri Darmon (McGill), DirectorAlgebraic number theory, arithmetic geometry,L-functions, Diophantine equations, elliptic curvesHugo Chapdelaine (Laval)Algebraic number theory, algebraic geometryChris J. Cummins (Concordia)Group theory, modular functions, moonshineChantal David (Concordia)Analytic number theory, L-functionsJean-Marie De Koninck (Laval)Analytic number theory: distribution of prime num-bers, factorization of numbers, asymptotic behaviourof arithmetic functions, Riemann zeta functionDavid S. Dummit (Vermont)Algebraic number theory, arithmetic algebraic geome-try, computational mathematicsDavid Ford (Concordia)Computational number theory, algorithmic numbertheoryJayce R. Getz (McGill)Number theoryEyal Z. Goren (McGill)Arithmetic geometry, algebraic number theory, mod-

uli spaces of abelian varieties, Hilbert modular forms,p-adic modular formsAndrew Granville (Montréal)Analytic number theory, arithmetic geometry, combi-natoricsHeekyoung Hahn (McGill)Eisenstein series, L-functions, trace formula, q-series,theta functions and partitionsAdrian Iovita (Concordia)Number theory, p-adic cohomologyOlga Kharlampovich (McGill)Combinatorial group theory and Lie algebrasHershy Kisilevsky (Concordia)L-functions, Iwasawa theory, elliptic curves, class fieldtheoryJohn Labute (McGill)Pro-p-groups, Lie algebras, Galois theory

Matilde Lalín (Montréal)Mahler measures, L-functions, zeta functionsClaude Levesque (Laval)Algebraic number theory, units, class number, cyclo-tomic fieldsMichael Makkai (McGill)Mathematical logicJohn McKay (Concordia)Computational group theory, sporadic groups, compu-tation of Galois groupsM. Ram Murty (Queen’s)Number theory: Artin’s conjecture, elliptic curves,modular forms, automorphic forms, Langlands pro-gram, Selberg’s conjectures, sieve methods, cryptogra-phy

Damien Roy (Ottawa)Transcendental number theoryPeter Russell (McGill)Algebraic geometryFrancisco Thaine (Concordia)Cyclotomic fields, cyclotomy, rational points on curves

CIRGET — Centre Interuniversitaire de Recherches en Géométrie et Topolo-gie

Description

Geometry and topology are fundamental disciplinesof mathematics whose richness and vitality, evidentthroughout human history, reflect a deep link to our

experience of the universe. They are a focal point ofmodern mathematics and indeed several domains ofmathematics have recently shown a strong trend to-wards a geometrization of ideas and methods: twocases in point are mathematical physics and number

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theory. CIRGET, based at UQAM, is composed of sev-enteen full members, four associate members, and alarge number of postdoctoral fellows and graduate stu-dents working in this broad field. The main themes tobe pursued in the coming years include the topologicalclassification of 3-dimensional manifolds; the quanti-zation of Hitchin systems and the geometric Langlandsprogram; the classification of special Kähler metrics;the study of symplectic invariants, especially in dimen-sion 4; non-linear partial differential equations in Rie-mannian geometry, convex geometry, and general rel-ativity; and Hamiltonian dynamical systems.

News and highlights

In 2012–2013 CIRGET and its members prepared andorganized three major events: the 2012–2013 ThematicYear; the short program on Rational Points, RationalCurves and Entire Holomorphic Curves on ProjectiveVarieties; and the SMS 2013 Summer School. With theCRM, CIRGET was able to leverage additional fund-ing from a number of international sources, includingover $200,000 from the NSF to support young Ameri-can mathematicians who participated in the activities.Nine of CIRGET’s doctoral students and PDFs finish-ing in 2012–2013 have obtained positions (tenure-trackor permanent): two in Canada, one in Scotland, one inAustralia, and 5 in France. In the 2012–2013 academicyear one undergraduate student, 25 M.Sc. students, 30Ph.D. students, and 24 postdoctoral fellows were su-pervised or cosupervised by CIRGET members.

Members of the Laboratory

Regular members

Vestislav Apostolov (UQAM), DirectorComplex geometry, Kähler geometrySteven Boyer (UQAM)Topology of manifolds, low-dimensional geometry andtopologyAbraham Broer (Montréal)Algebraic transformation groups, invariant theoryVirginie Charette (Sherbrooke)Discrete group actions on affine varieties, Lorentzmanifolds, Riemann surfaces discretization, discretedifferential geometryOlivier Collin (UQAM)Invariants of knots and 3-manifolds arising from globalanalysis

Octav Cornea (Montréal)Algebraic topology, dynamical systemsPengfei Guan (McGill)Partial differential equations, geometric analysis, sev-eral complex variablesJacques Hurtubise (McGill)Algebraic geometry, integrable systems, gauge theory,moduli spacesAndré Joyal (UQAM)Algebraic topology, category theoryNiky Kamran (McGill)Geometric approach to partial differential equationsFrançois Lalonde (Montréal)Symplectic topology and geometry, global analysis onmanifolds, infinite dimensional transformation groupsSteven Lu (UQAM)Chern number inequalities, semistability of tensorialsheaves, log jets, log and hyperbolic geometry, alge-braic degeneracyIosif Polterovich (Montréal)Geometric analysis, spectral theory, functional analy-sis, differential geometry, partial differential equationsFrédéric Rochon (UQAM)Geometric analysis, global analysis on singular spaces,index theory on manifolds with boundaryPeter Russell (McGill)Algebraic geometry

Johannes Walcher (McGill)Mirror symmetry for open strings, nongeometricstring compactifications

Daniel T. Wise (McGill)Geometric group theory, low-dimensional topology

Associate members

S. Twareque Ali (Concordia)Coherent states, wavelets, quantization techniques,harmonic analysis, Wigner functionsJohn Harnad (Concordia)Mathematical physics, classical and quantum physics,geometrical methods, integrable systems, group theo-retical methods, random matrices, isomonodromic de-formations, isospectral flowsDmitry Jakobson (McGill)Pure mathematics, global analysis, spectral geometry,quantum chaos, harmonic analysis, eigenvalues andeigenfunctionsJohn A. Toth (McGill)Microlocal analysis, partial differential equations

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GIREF — Groupe Interdisciplinaire de Recherche en Éléments Finis

Description

The recent advances in computer hardware and soft-ware allow researchers to model and simulate physi-cal phenomena whose complexity is unheard of. Theseproblems are characterized by nonlinear laws, non-differentiable friction laws, large-deformation geome-tries, complex solid-solid or fluid-solid interactions,problems in multiphysics, etc. Such problems can befound everywhere in industrial environments, espe-cially in the design and fabrication of high-technologyproducts. Thus the members of GIREF (“Groupe In-terdisciplinaire de Recherche en Éléments Finis,” orin English “Interdisciplinary Research Group in FiniteElement Methods”) aim to develop original numeri-cal methods for solving cutting-edge industrial prob-lems in nonlinear mechanics. Their work concern puremathematics, computer science, software engineering,and engineering. The GIREF members propose gen-eral methods that can be used for diverse industrialapplications. The some 27 member researchers reflectthe interdisciplinary nature of the Laboratory and arebased at the Université Laval, the École Polytechniquede Montréal, as well as the Universities of Moncton,Ottawa, and Alberta.

News and highlights

GIREF is active in fluid and solid mechanics. Its in-dustrial partnerships, notably in the fields of pneumat-ics and manufacturing of wood-based products, give avery applied flavour to the research carried out by itsmembers (especially within the NSERC Research Chairin High Performance Scientific Computing held by A.Fortin). GIREF also applies mathematical techniques toproblems from biology. GIREF was the official host ofthe Annual Meeting of the Canadian Applied and In-dustrial Mathematics Society (CAIMS), which gatheredover 200 participants in Québec City in June 2013. In2013 GIREF recruited N. Doyon, an expert on digitalmodelling in the neurosciences, who is now a memberof the biomedical modelling group along with Garon(École Polytechnique), Delfour (Université de Mont-réal), and Bourgault (University of Ottawa). In the2012–2013 academic year one undergraduate student,12 M.Sc. students, 11 Ph.D. students, and 4 postdoctoralfellows were carrying out research at GIREF.

Regular members

André Fortin (Laval), DirectorFinite elements method, instationary viscous flows,mixing problemsAndré Garon (Polytechnique Montréal), Deputy Di-rectorThermohydraulics, fluid mechanics, finite elementsmethod, hydraulic turbines, mechanics of biofluids:stents and pumps

Youssef Belhamadia (Alberta)Mathematical modelling and numerical simulation ofphase change problems, adaptive meshing for insta-tionary problems in 2 and 3 dimensions, numericalmodelling of cryosurgery, numerical modelling of theelectromechanical wave in the heartYves Bourgault (Ottawa)Computational fluid dynamics, numerical methods, fi-nite elements method, mathematical modelling, me-chanics of continuous mediaMichel C. Delfour (Montréal)Control, optimization, design, shells, calculus, biome-chanicsMichel Fortin (Laval)Numerical analysis of partial differential equations,numerical methods in fluid mechanics, optimizationand optimal control for partial differential equationsRobert Guénette (Laval)Numerical methods in non-Newtonian fluid mechan-ics, rheological models, Hamiltonian formulationHassan Manouzi (Laval)Numerical analysis, applications of mathematics to en-gineeringDominique Pelletier (Polytechnique Montréal)Fluid mechanics and heat transfer, finite elementsmethod, adaptive finite elements methods for com-pressible and incompressible flows, modelling and sim-ulation of laminar and turbulent viscous flows, mod-elling and simulation of fluid-structure interactionsRoger Pierre (Laval)Numerical analysis of partial differential equationsJosé Urquiza (Laval)Numerical analysis, control of partial differential equa-tions

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Associate members

Pierre Blanchet (FPInnovations)Nanotechnology for wood products

Alain Charbonneau (UQO)Numerical simulation of optical wave guides, finite ele-ments method, numerical methods, statistical machinetranslation, automated text categorization

Alain Cloutier (Laval)Forestry, forest engineeringMarie-Laure Dano (Laval)Mechanics and production of composite materials, in-telligent mechanical systemsClaire Deschênes (Laval)Axial hydraulic turbinesGuy Dumas (Laval)Mechanical engineering, physics of fluidsMohamed Farhloul (Moncton)Finite elements and finite volumes method, partial dif-ferential equations, applications of the mixed finite el-ements method to fluid mechanics, numerical analysisMarie-Isabelle Farinas (UQAC)Modelling, numerical simulation, computational fluidmechanics, design of turbo engines (cardiac pump), op-timization

Vincent François (UQTR)Integration of the finite elements method intocomputer-aided designYves Fortin (Laval)Forestry, forest engineeringAugustin Gakwaya (Laval)Aerospatial and aeronautical engineering, numericalmodelling, computer-assisted designGuy Gendron (Laval)Composite materials, optimization and modelling ofstructuresJean-François Hétu (NRC-IMI)Numerical modelling of processesJean-Loup Robert (Laval)Numerical models of free surface flows, transport anddiffusion models with stochastic components, unifiedmodelling in a saturated and aerated environmentYves Secretan (INRS-ETE)Numerical methods for finite elements, mesh genera-tion and adaptation, error estimation, hydrodynamicsin 2 dimensions, advection-diffusion phenomenaRenéTherrien (Laval)Underground water flows, hydrology, geothermics

LaCIM — Laboratoire de Combinatoire et d’Informatique Mathématique

Description

LaCIM (French acronym meaning “Combinatorics andMathematical Computer Science Laboratory”) is hometo mathematics and theoretical computer science re-searchers whose interests comprise discrete mathe-matics and the mathematical aspects of computer sci-ence. Founded in 1989, LaCIM includes 15 regularmembers, 5 associate members, and 16 collaboratingmembers. It welcomes postdoctoral fellows and its reg-ular members supervise or cosupervise many M.Sc.and Ph.D. students, as well as undergraduate and cegepsummer research students. Many renowned mathe-maticians visit LaCIM and collaborate with its mem-bers in the following areas: enumerative and bijec-tive combinatorics, theory of species, algebraic com-binatorics, combinatorics of finite and infinite words,discrete geometry, theory of languages and automata,Gray codes, bioinformatics, and combinatorial opti-mization.

News and highlights

The main research areas of LaCIM are algebraic com-binatorics, bioinformatics, and mathematical computerscience. The support of the CRM has made it possiblefor 8 full-time postdocs to be involved in the LaCIMresearch activities, on top of all the graduate studentsand undergraduate trainees. It is noteworthy that 25%of the talks at this year’s edition of FPSAC (the main in-ternational conference in algebraic combinatorics anda very selective one) have coauthors who are (currentor past) PDFs or students of LaCIM. The expertise ofthe CRM in organizing meetings helped LaCIM holdan international conference in Cetraro, Italy, in July2013 (“Words, Codes, and Algebraic Combinatorics – Aconference in honor of Christophe Reutenauer’s 60thbirthday”). In the 2012–2013 academic year 18 M.Sc.students, 28 Ph.D. students, and 10 postdoctoral fel-lows were supervised or cosupervised by LaCIM mem-bers.

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Centre de recherches mathématiqes

Members of the Laboratory

Regular members

Srečko Brlek (UQAM), DirectorCombinatorics of words, algorithmics

Ibrahim Assem (Sherbrooke)Representation theory

Anne Bergeron (UQAM)Bioinformatics

François Bergeron (UQAM)Combinatorics, algebra, representations of finitegroups

Thomas Brüstle (Sherbrooke & Bishop’s)Algebraic combinatorics, cluster algebras, triangula-tions of surfaces, stochastic differential equations,mathematical models in finance

Cedric Chauve (Simon Fraser & UQAM)Enumerative combinatorics, trees, bioinformatics

Sylvie Hamel (Montréal)Bioinformatics and algorithms, theory of languagesand automata, algebraic combinatorics

Christophe Hohlweg (UQAM)Algebra, algebraic combinatorics, convex geometry

Gilbert Labelle (UQAM)Enumerative combinatorics, analysis

Shiping Liu (Sherbrooke)Representation theory

Vladimir Makarenkov (UQAM)Computational biology, mathematical classification

Marni Mishna (Simon Fraser)Algorithms and enumerative, analytical, and algebraiccombinatorics

Christophe Reutenauer (UQAM)Algebraic combinatorics, noncommutative algebra, au-tomata theory, coding theory, free algebras

Franco Saliola (UQAM)Algebraic combinatorics, group representations

Timothy R. S. Walsh (UQAM)Algorithmics, enumerative combinatorics, graph the-ory

Associate members

Pierre Lalonde (Maisonneuve)Enumerative and bijective combinatorics, alternatingsign matrices, enumeration of involutions with respect

to various parameters, use of Pfaffians and determi-nants in enumeration

Cédric Lamathe (UQAM)Combinatorics of tree-like structures, theory ofspecies, indicator series of partially labeled structuresand asymmetric structures

Luc Lapointe (Talca)Algebraic combinatorics, symmetric functions, inte-grable systems, supersymmetries

Odile Marcotte (UQAM & CRM)Combinatorial optimization, integer programming,graph theory

Dominic Rochon (UQTR)Complex analysis, hypercomplex numbers

Collaborating members

Marcello Aguiar (Texas A&M)Algebraic combinatorics, non-commutative algebra,Hopf algebras and quantum groups, category theory

Robert Bédard (UQAM)Representations of finite groups, Lie theory

Luc Bélair (UQAM)Mathematical logic, model theory

Nantel Bergeron (York)Applied algebra

Pierre Bouchard (UQAM)Commutative algebra, algebraic geometry and combi-natorics

Michel Bousquet (Vieux-Montréal)Enumeration of combinatorial structures, planar mapsand cacti, theory of species, Lagrange inversion formu-las

Yves Chiricota (UQAC)Computer graphics, mathematical methods in com-puter graphics, combinatorics, computational geome-try, symbolic computation

Sylvie Corteel (LIAFA & CNRS)Enumerative and bijective combinatorics, partitions ofintegers, q-series

Adriano Garsia (UC San Diego)Algebraic combinatorics, symmetric functions, har-monic and coinvariant spaces, quasiharmonic andquasi-invariant functions

Alain Goupil (UQTR)Combinatorics, algebra, linear representations ofgroups, symmetric group

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Research Laboratories

André Joyal (UQAM)Algebraic topology, category theory

Jacques Labelle (UQAM)Combinatorics, topology

Louise Laforest (UQAM)Data structures, combinatorics, asymptotic analysis,quaternary trees

Daniel Lemire (TÉLUQ)Database theory, data warehousing, multidimensional

databases (OLAP), data mining, time series, collabora-tive filtering, information retrieval

Simon PlouffeInteger sequences, generalized expansions of real num-bers

Xavier G. Viennot (Bordeaux 1)Enumerative, algebraic, and bijective combinatorics,interactions between combinatorics, theoretical infor-matics, and theoretical physics

Mathematical Analysis

Description

At the same time classical and central to modern math-ematics, analysis involves the study of continuous sys-tems, from dynamical systems to solutions of par-tial differential equations and spectra of operators. In2012–2013 the Laboratory included 28 regular and 10associate members working at ten different universi-ties in Canada, the United Kingdom, and France. Themembers of the Laboratory work in the following ar-eas: harmonic analysis, complex analysis and severalcomplex variables, potential theory, functional analy-sis, Banach algebras, microlocal analysis, analysis onmanifolds, nonsmooth analysis, spectral theory, partialdifferential equations, geometric analysis, ergodic the-ory and dynamical systems, control theory, mathemat-ical physics, applied mathematics, probability, nonlin-ear analysis, nonlinear differential equations, topolog-ical methods in differential equations, fluid dynamics,and turbulence.

News and highlights

As is typical for the Mathematical Analysis Labora-tory, the year 2012–2013 featured many collaborativeand training activities. Another activity was the highlysuccessful “Workshop on Invariant Subspaces of theShift Operator” (in August 2013). In Montréal the long-running Analysis Seminar is now taking place at dif-ferent Montréal universities and has been renamedthe “Montréal Analysis Seminar”. French researchersFricain, Pillet, and Panati visited the Laboratory and agroup of five McGill students spent 6 weeks at the IHPin Paris and two weeks at a summer school in Autran.Y. Canzani, a 2013 Ph.D. from McGill supervised by D.Jakobson and J. Toth, is now a Benjamin Pierce Fellowat Harvard. The 2013 Carl Herz Prize was awarded to

M. Najafi Ivaki, who obtained his Ph.D. at Concordiaunder the supervision of A. Stancu. In the 2012–2013academic year 3 undergraduate students, 36 M.Sc. stu-dents, 39 Ph.D. students, and 19 postdoctoral fellowswere supervised or cosupervised by members of theMathematical Analysis Laboratory.

Members of the Laboratory

Regular members

Dmitry Jakobson (McGill), DirectorPure mathematics, global analysis, spectral geometry,quantum chaos, harmonic analysis, eigenvalues andeigenfunctions

Line Baribeau (Laval)Complex and functional analysis, Banach algebras,holomorphic iterations, discrete groups

Abraham Boyarsky (Concordia)Dynamical systems

Francis H. Clarke (Lyon 1)Nonlinear and dynamic analysis, control theory, calcu-lus of variations

Galia Dafni (Concordia)Harmonic analysis, partial differential equations, com-plex variables

Donald A. Dawson (Carleton)Probability, stochastic processes

S. W. Drury (McGill)Harmonic analysis, matrix theory

Richard Fournier (Dawson)Complex analysis, function theory

Marlène Frigon (Montréal)Nonlinear analysis, differential equations, fixed pointtheory, critical point theory, multivalent analysis

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Centre de recherches mathématiqes

Paul M. Gauthier (Montréal)Complex analysis, holomorphy, harmonicity, analyticapproximation

Pawel Gora (Concordia)Ergodic theory, dynamical systems, fractal geometry

Frédéric Gourdeau (Laval)Banach algebras, cohomology, amenability, functionalanalysis

Vojkan Jakšić (McGill)Mathematical physics, quantum statistical mechanics,random Schrödinger operators

Tomasz Kaczynski (Sherbrooke)Topological methods, Conley index, applications to dy-namical systems

Ivo Klemes (McGill)Harmonic analysis, trigonometric series

Alexey Kokotov (Concordia)Spectral geometry of Riemann surfaces, hyperbolicpartial differential equations

Paul Koosis (McGill)Harmonic analysis

Javad Mashreghi (Laval)Complex analysis, harmonic analysis, Hardy spaces

Iosif Polterovich (Montréal)Geometric analysis, spectral theory, functional analy-sis, differential geometry, partial differential equations

Thomas J. Ransford (Laval)Complex and harmonic analysis, functional analysisand theory of operators, spectral analysis, potentialtheory

Dominic Rochon (UQTR)Complex analysis, hypercomplex numbers

Jérémie Rostand (Laval)Complex analysis, experimental mathematics

Christiane Rousseau (Montréal)Dynamical systems, bifurcations, qualitative theory,polynomial systems, analytic invariants, integrablesystems

Dana Schlomiuk (Montréal)Global analysis, dynamical systems, singularities, bi-furcations, algebraic curves, primary integral

Robert Seiringer (McGill)Many-body quantum systems, Bose-Einstein conden-sates

Alexander Shnirelman (Concordia)Applications of geometric analysis to fluids and “weak”solutions of the Euler and Navier-Stokes equations

Alina Stancu (Concordia)Geometric analysis

Ron J. Stern (Concordia)Functional analysis and theory of operators, linear andnonlinear systems, non-smooth analysis, stability, op-timal order

John A. Toth (McGill)Spectral theory, semi-classical analysis, microlocalanalysis, Hamiltonian mechanics

Associate members

Octavian Cornea (Montréal)Algebraic topology, dynamical systems

Richard Duncan (Montréal)Ergodic theory, martingale theory, probability theoryin Banach spaces

Kohur Gowrisankaran (McGill)Potential theory

Pengfei Guan (McGill)Partial differential equations, geometric analysis, sev-eral complex variables

John Harnad (Concordia)Mathematical physics, classical and quantum physics,geometrical methods, integrable systems, group theo-retical methods, random matrices, isomonodromic de-formations, isospectral flows

Niky Kamran (McGill)Geometric approach to partial differential equations

Dmitry Korotkin (Concordia)Integrable systems, isomonodromic deformations,classical and quantum gravity, Frobenius varieties

Nilima Nigam (Simon Fraser)Applied analysis, numerical methods in electromag-netism

Yiannis N. Petridis (University College London)Automorphic forms and their spectral theory, analyticnumber theory, spectral and scattering theory of man-ifolds

Samuel Zaidman (Montréal)Functional analysis and differential equations in ab-stract spaces, pseudo-differential operators

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Research Laboratories

Mathematical Physics

Description

The mathematical physics group is one of the oldestand most active at the CRM. It consists of 18 regu-lar members, 10 local associate members, all full-timefaculty members at one of the participating universi-ties, and 7 external associate members working per-manently at universities and research laboratories inEurope, the U.S., or Mexico. The group carries out re-search in many of the most active areas of mathe-matical physics: coherent nonlinear systems in fluids,optics, and plasmas; classical and quantum integrablesystems; the spectral theory of random matrices; per-colation phenomena; conformal field theory; quantumstatistical mechanics; spectral and scattering theoryof random Schrödinger operators; quasi-crystals; rela-tivity; spectral transform methods; foundational ques-tions in quantization; asymptotics of eigenstates; co-herent states; wavelets; supersymmetry; the symmetryanalysis of PDEs and difference equations; representa-tion theory of Lie groups and quantum groups; and themathematical structure of classical and quantum fieldtheories.

News and highlights

Two of the Laboratory members, J. Hurtubise andJ. Walcher, were on the scientific committee of the2012–2013 Thematic Year and organized the workshop“Moduli spaces and their invariants in mathematicalphysics.” R. Brandenberger organized the workshop“Adventures in Superspace” in April 2013: its partici-pants included nearly all the pioneers in supersymmet-ric field theory. Several prizes and distinctions wereawarded to Laboratory members recently: L. Vinet wasawarded the CAP–CRM Prize in 2012; R. Seiringer wasawarded an NSERC E. W. R. Steacie Memorial Fellow-ship in 2012; J. Walcher was appointed to a CanadaResearch Chair (Tier II); and M. Grundland obtaineda “Research fellowship” from the Digiteo Foundation.In the 2012–2013 academic year 10 undergraduate stu-dents, 29 M.Sc. students, 47 Ph.D. students, and 30 post-doctoral fellows were supervised or cosupervised bymembers of the Mathematical Physics Laboratory.

Members of the Laboratory

Regular members

John Harnad (Concordia), DirectorMathematical physics, classical and quantum physics,geometrical methods, integrable systems, group theo-retical methods, random matrices, isomonodromic de-formations, isospectral flows

S. Twareque Ali (Concordia)Coherent states, wavelets, quantization techniques,harmonic analysis, Wigner functions

Marco Bertola (Concordia)Axiomatic quantum field theory, invariant theory ofdiscrete groups, random matrices, isomonodromic de-formations

Robert Brandenberger (McGill)Theoretical Cosmology

Keshav Dasgupta (McGill)Heavy ion collision theory in the energy range30MeV/nucleon to many GeV/nucleon

Alfred Michel Grundland (UQTR)Symmetry of differential equations in physics

Richard L. Hall (Concordia)Spectra of Schrödinger, Klein-Gordon, Dirac, andSalpeter operators, many-body problems, relativis-tic scattering theory, iterative solution to ODEs andboundary-value problems

Jacques Hurtubise (McGill)Algebraic geometry, integrable systems, gauge theory,moduli spaces

Véronique Hussin (Montréal)Group theory, Lie algebras and applications in physics,supersymmetries in classical and quantum mechanics

Dmitry Korotkin (Concordia)Integrable systems, isomonodromic deformations,classical and quantum gravity, Frobenius varieties

Pierre Mathieu (Laval)Conformal field theory, classical and quantum inte-grable systems, affine Lie algebras

Manu Paranjape (Montréal)Theoretical particle physics: field theory, solitons, non-commutative geometry, alternative gravity

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Centre de recherches mathématiqes

Jiří Patera (Montréal)Applications of group theory, quasi-crystals, Lie alge-bras

Yvan Saint-Aubin (Montréal)Conformal field theory, statistical mechanics, 2-dimensional phase transition model

Robert Seiringer (McGill)Quantum many-body systems, Bose-Einstein conden-sates, Ginzburg-Landau theory, Gross-Pitaevskii the-ory, bosons

Vasilisa Shramchenko (Sherbrooke)Frobenius manifolds, integrable systems, Riemann-Hilbert problems, isomonodromic deformations of sys-tems of linear differential equations, function theoryon Riemann surfaces

Luc Vinet (Montréal)Symmetry properties of systems, special functions

Johannes Walcher (McGill)Mirror symmetry for open strings, non-geometricstring compactifications

Pavel Winternitz (Montréal)Methods of group theory in physics, nonlinear phe-nomena, symmetries of difference equations, superin-tegrability

Associate members

Robert Conte (CEA/Saclay)Integrable and partially integrable systems, Painlevéanalysis, exact solutions, finite difference equations

Chris Cummins (Concordia)Group theory, modular functions, moonshine

Stéphane Durand (Édouard-Montpetit)Classical and quantum physics, mathematical physics,symmetries, parasupersymmetries, fractional super-symmetries, KdV equations, quantum mechanics, rel-ativity

Bertrand Eynard (CEA/Saclay)Matrix models, integrable systems, string theory, rela-tionship between matrix models, integrability, and al-gebraic geometry

Jean-Pierre Gazeau (Paris Diderot)Coherent states, wavelets, relativistic quantum frames,symmetry groups for beta-lattices

Alexander Its (IUPUI)Soliton theory, integrable systems, special functions,mathematical physics

Dmitry Jakobson (McGill)Pure mathematics, global analysis, spectral geometry,quantum chaos, harmonic analysis, eigenvalues andeigenfunctions

Vojkan Jakšić (McGill)Mathematical physics, quantum statistical mechanics,random Schrödinger operators

Niky Kamran (McGill)Geometric approach to partial differential equations

François Lalonde (Montréal)Symplectic topology and geometry, global analysis onmanifolds, Hamiltonian systems

Decio Levi (Roma Tre)Symmetries of differential and difference equations,integrable nonlinear equations on the lattice and re-ductive perturbation theory on the lattice

Alexander Maloney (McGill)String theory, particle physics, cosmology, quantumgravity

Alexander Shnirelman (Concordia)Applications of geometrical analysis to fluids and“weak” solutions of the Euler and Navier-Stokes equa-tions

John A. Toth (McGill)Spectral theory, semi-classical analysis, microlocalanalysis, Hamiltonian mechanics

Alexander Turbiner (UNAM, Mexico)Quantum mechanics, atomic and molecular physics,variational methods

Carolyne M. Van Vliet (Montréal & Miami)Non-equilibrium statistical mechanics, fluctuationsand stochastic processes, quantum transport in con-densed matter, electronic behaviour in submicronquantum devices

Peter Zograf (Steklov Mathematical Institute, St. Pe-tersburg)Geometry of moduli spaces, automorphic forms, spec-tral geometry

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Research Laboratories

PhysNum

Description

Applied mathematics now plays an important rolein the biomedical field and especially the neuro-sciences. The research activity at PhysNum has twomain themes: pharmacometrics and brain imaging. Inparticular

• Jean-Marc Lina (École de technologie supérieure)and Habib Benali (Université Pierre et Marie Curie)work on the multimodal imaging of the spinal cord;

• Lina and Christophe Grova (McGill University)work on multiresolution and multimodal imaging inmagneto-electrophysiology;

• Benali and Maxime Descoteaux (Université de Sher-brooke) study models of the anatomical and func-tional connectivity of the brain;

• Grova studies neurovascular models in epilepsy;

• Lina studies sparse representations, inverse prob-lems, and brain wave synchronization; and

• Lina analyzes scale-invariant processes in electro-physiology.

Fahima Nekka and her team conduct research in phar-macometrics, a discipline whose goal is to interpretand describe pharmacological phenomena in a quanti-tative manner, so as to support rational therapeutic de-cisions and improvement of patient health. They havedeveloped a whole framework of probabilistic pharma-cometrics in which different sources of variability andthe nonlinearity of the system are accounted for. Theteam is working on compliance metrics and rankingand on direct and inverse problems related to patientdrug behaviour and the therapeutic effect of drugs. Itis conceiving tools that shed new light on drug devel-opment and evaluation in terms of efficacy and bioe-quivalence; revisiting classical concepts in pharmacol-ogy and updating their formulation; developing mod-els for drug interactions; integrating physiology withbehaviour to create a real fingerprint of drugs; inte-grating advanced hematopoietic models with PK/PD

to improve concurrent therapy consisting of oncologi-cal drugs and their adjuvants.

News and highlights

In October 2013 Ciuciu and Lina prepared a work-shop held in October 2013, the Workshop on Scale-free Dynamics and Networks in Neurosciences. Phys-Num partners with the Athena team within INRIA(Sophia-Antipolis, France) and an international labo-ratory, LINeM, within INSERM (the French Health Re-search Institute). In the 2012–2013 academic year 18M.Sc. students, 25 Ph.D. students, and 8 postdoctoralfellows were supervised or cosupervised by PhysNummembers.

Members of the Laboratory

Regular members

Jean-Marc Lina (ÉTS), DirectorWavelets, statistical modelling and brain imaging, ma-chine learning

Alain Arnéodo (ÉNS Lyon & CNRS)Fractals and wavelets

Habib Benali (UPMC)Quantitative analysis in brain imaging, medical imag-ing and multimodal systems

Maxime Descoteaux (Sherbrooke)Medical imaging, image analysis and processing, com-puter vision, applied mathematics

Christophe Grova (McGill)Statistical signal processing, localization of epilepticspikes using distributed sources modelling, and mul-timodal analysis of EEG source localization and simul-taneous EEG-fMRI data analysis

Frédéric Lesage (Polytechnique Montréal)Conformal theory, integrable systems, inverse prob-lems, optical imaging

Fahima Nekka (Montréal)Pharmacokinetics, development of mathematical toolsfrom fractal geometry and harmonic analysis for ex-tracting information, applications to pharmacologyand medicine

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Centre de recherches mathématiqes

Statistics

Description

Statistics is central to many endeavours in society.Be it through surveys from sampling, clinical trials tostudy various biomedical treatments, or experimentaldesigns in agriculture or industry, statistical method-ology can be found everywhere in science. Recently,statistics has undergone a revolution in its techniquesand approaches. This revolution has been driven bythe need to analyze very large data sets and data withmore complex structure, and by the advent of power-ful computers. For example, statistical methodology isnow addressing problems whose structure is very com-plex, such as the analysis of brain images or genomedata, and new methodology is being developed, suchas data mining, for large data sets. Note that the nameof the Laboratory must be interpreted broadly, as someof its members are actuaries, probabilists, or biostatis-ticians.

One of the aims of the Laboratory is to structure theQuébec statistical community so that it can participatein this revolution at a time when an important renewalof academic personnel is taking place. This structure al-lows the Québec community to participate in Canada-wide programs organized by the three Canadian math-ematics institutes. The Laboratory is formed of theleaders of the Québec school of statistics, who workon topics such as statistical learning and neural net-works, survey sampling, analysis of functional data,statistical analysis of images, dependence structures,Bayesian analysis, analysis of time series and financialdata, and resampling methods.

News and highlights

Nowadays the analysis of unimaginably vast amountsof data poses significant challenges, both methodolog-ically and in terms of HQP training. The Laboratorycontributes to this effort through an average of 150scientific publications per year and extensive graduatesupervision. This year 130 M.Sc. and 86 Ph.D. studentswere supervised or co-supervised by Laboratory mem-bers; those who completed their studies found imme-diate employment after their studies. Of the 10 PDFs,four found tenure-track positions in Canada while thesix others are still in training. The CRM provided finan-cial support for the Montreal Spring School of “Pop-ulation Genomics and Genetic Epidemiology” (May

2013), the “3rd Graduate Student Workshop on Actuar-ial and Financial Mathematics” (December 2013), andthe “Concordia Workshop on Nonparametric CurveSmoothing” (December 2013).

Members of the Laboratory

Regular members

Louis-Paul Rivest (Laval), DirectorLinear models, robustness, directional data, sampling,applications in finance

Belkacem Abdous (Laval)Biostatistics, health research methodology, construc-tion and validation of measuring tools in the healthsector

Jean-François Angers (Montréal)Decision theory, Bayesian statistics, robustness withrespect to prior information, function estimation

Masoud Asgharian (McGill)Survival analysis, change-point problems, simulatedannealing and its variants, optimization

Yoshua Bengio (Montréal)Statistical learning algorithms, neural networks, nu-cleus models, probabilistic models, data mining, appli-cations in finance and statistical language modelling

Martin Bilodeau (Montréal)Multivariate analysis, decision theory, asymptoticmethods

Yogendra P. Chaubey (Concordia)Sampling, linear models, resampling, survival analysis

Pierre Duchesne (Montréal)Time series, sampling, multivariate analysis

Thierry Duchesne (Laval)Survival analysis, longitudinal data analysis, missingdata, modelling of losses, insurance of catastrophicincidents, nonparametric inference, model selection,warranty

Debbie J. Dupuis (HEC Montréal)Extreme values, robustness

Sorana Froda (UQAM)Nonparametric methods in function estimation, ap-plications of stochastic modelling in biology andmedicine

Christian Genest (McGill)Multidimensional data analysis, dependence measures,

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Research Laboratories

nonparametric statistics, decision theory, applicationsin actuarial science, finance, and psychology

Nadia Ghazzali (Laval)Multidimensional data analysis, neural networks andgenetic algorithms, applications in astrophysics andbiostatistics

Aurélie Labbe (McGill)Biostatistics and statistical genetics

Fabrice Larribe (UQAM)Statistical genetics and biostatistics

Christian Léger (Montréal)Resampling methods, adaptive estimation, model se-lection, robustness, applications in data mining

Brenda MacGibbon (UQAM)Mathematical statistics, decision theory, biostatistics

Éric Marchand (Sherbrooke)Statistical inference, Bayesian statistics, multivariateanalysis and probability

Alejandro Murua (Montréal)Data mining, machine learning, object recognition,signal processing, and various applications of statisticsand probability to bioinformatics and the social andhealth sciences

François Perron (Montréal)Decision theory, multidimensional data analysis,Bayesian statistics

James Ramsay (McGill)Functional data analysis, smoothing and nonparamet-ric regression, curve registration

Bruno Rémillard (HEC Montréal)Probability theory, empirical processes, time series,nonlinear filtering, applications in finance

Roch Roy (Montréal)Time series analysis, predictive methods, applicationsin econometrics and epidemiology

Arusharka Sen (Concordia)Statistical inference of truncated data, nonparametricfunction estimation

Russell Steele (McGill)Bayesian approaches to mixing modelling, multipleimputation

David Stephens (McGill)Bayesian statistics, Markov Chain Monte Carlo andapplications to bioinformatics, statistical genetics, andtime series analysis

Wei Sun (Concordia)Nonlinear filtering and its applications, stochasticanalysis, statistical inference, stochastic modelling

David B. Wolfson (McGill)Change-point problems, survival analysis, Bayesianstatistics, optimal design, applications in medicine

Associate members

Juli Atherton (McGill)Biostatistics, optimal Bayesian design, change-pointproblems, survival analysis, applications to genetics

Mylène Bédard (Montréal)Optimal scaling, Metropolis-Hastings algorithms

Anne-Catherine Favre (Laval)Statistical hydrology, analysis and modelling of timeseries

José Garrido (Concordia)Risk theory, insurance statistics

David Haziza (Montréal)Sampling theory, inference with missing data, robustinference

Lajmi Lakhal Chaïeb (Laval)Multidimensional analysis of survival data, analysis ofrecurrent events, semi-parametric models and incom-plete data

Geneviève Lefebvre (UQAM)Bayesian and computational statistics, biostatistics

Erica E. M. Moodie (McGill)Causal inference, optimal dynamic treatment regimes,longitudinal data, dose-response relationships

Manuel Morales (Montréal)Mathematical finance, applied stochastic processes,ruin theory, actuarial science, Lévy processes, math-ematics of insurance

Johanna Nešlehová (McGill)Multivariate analysis, dependence modelling, non-parametric and asymptotic statistics, multivariate ex-treme value theory, empirical processes, applicationsto biostatistics, neuroscience and risk management

Robert W. Platt (McGill)Biostatistics and statistical methods for pediatric andperinatal epidemiology.

Lea Popovic (Concordia)Probability theory and its applications to evolutionarybiology, population genetics, and cell biology

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Publications

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Publications

The CRM publishes monographs, lecture notes, proceedings, software, videos, and research reports. It hasseveral collections. The in-house collection (Les Publications CRM) offers titles in both English and French.

The CRM also has publishing agreements with the American Mathematical Society (AMS) and Springer. Since1992, two collections, edited by the CRM, have been published and distributed by the AMS. They are the CRMMonograph Series and the CRM Proceedings and Lecture Notes. Springer publishes the CRM Series in MathematicalPhysics. An asterisk preceding a publication indicates that its author is an Aisenstadt Chairholder.

Recent Titles

The following list of recent titles contains books thatappeared in 2012–2013 or that will be published soon.

American Mathematical SocietyCRM Monograph Series

Libor Šnobl & Pavel Winternitz, Classification andIdentification of Lie Algebras, to appear

Pavel Bleher & Karl Liechty, Random Matrices and theSix-Vertex Model, to appear.

Jean-Pierre Labesse & Jean-Loup Waldspurger, La For-mule des Traces Tordue d’après le Friday Morning Sem-inar, vol. 31, 2013.

American Mathematical SocietyCRM Proceedings & Lecture Notes

Galia Dafni, Robert John McCann & Alina Stancu(eds.), Analysis and Geometry of Metric Measure Spaces:

Lecture Notes of the 50th Séminaire de MathématiquesSupérieures (SMS), Montréal, 2011, vol. 56, 2013.

André Boivin & Javad Mashreghi (eds.), Complex Anal-ysis and Potential Theory, vol. 55, 2012.

American Mathematical SocietyContemporary Mathematics (Centre deRecherches Mathématiques Proceedings)

Chantal David, Matilde Lalín & Michelle Manes (eds.),Women in Numbers 2: Research Directions in NumberTheory, to appear.

Omid Amini, Matthew Baker & Xander Faber (eds.),Tropical and Non-Archimedean Geometry, to appear.

Previous Titles

American Mathematical SocietyCRM Monograph Series

Joseph H. Silverman, Moduli Spaces and Arithmetic Dy-namics, vol 30, 2012.

Marcelo Aguiar & Swapneel Mahajan, Monoidal Cate-gories, Species and Hopf Algebras, vol 29, 2010.

Saugata Ghosh, Skew-Orthogonal Polynomials and Ran-dom Matrix Theory, vol. 28, 2009.

Jean Berstel, Aaron Lauve, Christophe Reutenauer &Franco V. Saliola, Combinatorics on Words: ChristoffelWords and Repetitions in Words, vol. 27, 2008.

Victor Guillemin & Reyer Sjamaar, Convexity Proper-ties of Hamiltonian Group Actions, vol. 26, 2005.

*Andrew J. Majda, Rafail V. Abramov & Marcus J.Grote, InformationTheory and Stochastics for MultiscaleNonlinear Systems, vol. 25, 2005.

Dana Schlomiuk, Andrei A. Bolibrukh, Sergei Yako-venko, Vadim Kaloshin & Alexandru Buium, On Finite-ness in Differential Equations and Diophantine Geome-try, vol. 24, 2005.

Prakash Panangaden & Franck van Breugel (eds.),Mathematical Techniques for Analyzing Concurrent andProbabilistic Systems, vol. 23, 2004.

Montserrat Alsina & Pilar Bayer, Quaternion Orders,Quadratic Forms, and Shimura Curves, vol. 22, 2004.

Andrei Tyurin, Quantization, Classical and QuantumField Theory and Theta Functions, vol. 21, 2003.

Joel Feldman, Horst Knörrer & Eugene Trubowitz, Rie-mann Surfaces of Infinite Genus, vol. 20, 2003.

*Laurent Lafforgue, Chirurgie des grassmanniennes,vol. 19, 2003.

*George Lusztig, Hecke Algebras with Unequal Param-eters, vol. 18, 2003.

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Centre de recherches mathématiqes

Michael Barr, Acyclic Models, vol. 17, 2002.

*Joel Feldman, Horst Knörrer & Eugene Trubowitz,Fermionic Functional Integrals and the RenormalizationGroup, vol. 16, 2002.

Jose I. Burgos, The Regulators of Beilinson and Borel,vol. 15, 2002.

Eyal Z. Goren, Lectures onHilbertModular Varieties andModular Forms, vol. 14, 2002.

Michael Baake & Robert V. Moody (eds.), Directions inMathematical Quasicrystals, vol. 13, 2000.

Masayoshi Miyanishi, Open Algebraic Surfaces, vol. 12,2001.

Spencer J. Bloch, Higher Regulators, Algebraic K-Theory, and Zeta Functions of Elliptic Curves, vol. 11,2000.

James D. Lewis, A Survey of the Hodge Conjecture, 2ndedition, vol. 10, 1999 (with an appendix from B. BrentGordon).

*Yves Meyer, Wavelets, Vibrations and Scaling, vol. 9,1997.

*Ioannis Karatzas, Lectures on Mathematics of Finance,vol. 8, 1996.

John Milton, Dynamics of Small Neural Populations,vol. 7, 1996.

*Eugene B. Dynkin, An Introduction to BranchingMeasure-Valued Processes, vol. 6, 1994.

Andrew M. Bruckner, Differentiation of Real Functions,vol. 5, 1994.

*David Ruelle, Dynamical Zeta Functions for PiecewiseMonotone Maps of the Interval, vol. 4, 1994.

V. Kumar Murty, Introduction to Abelian Varieties,vol. 3, 1993.

Maximilian Ya. Antimirov, Andrei A. Kolyshkin &Rémi Vaillancourt, Applied Integral Transforms, vol. 2,1993.

*Dan V. Voiculescu, Kenneth J. Dykema & AlexandruNica, Free Random Variables, vol. 1, 1992.

American Mathematical SocietyCRM Proceedings & Lecture Notes

Daniel Daigle, Richard Ganong & Mariusz Koras (eds.),Affine Algebraic Geometry: The Russell Festschrift,vol. 54, 2011.

Bradd Hart, Thomas G. Kucera, Anand Pillay, Philip J.Scott & Robert A. G. Seely (eds.), Models, Logics, andHigher-Dimensional Categories, vol. 53, 2011.

Dmitry Jakobson, Stéphane Nonnenmacher & IosifPolterovich (eds.), Spectrum and Dynamics, vol. 52,2010.

Javad Mashreghi, Thomas Ransford & KristianSiep (eds.), Hilbert Spaces of Analytic Functions, vol. 51,2010.

P. Robert Kotiuga (ed.), A Celebration of the Mathemat-ical Legacy of Raoul Bott, vol. 50, 2009.

Miguel Abreu, François Lalonde & Leonid Poltero-vich (eds.), New Perspectives and Challenges in Symplec-tic Field Theory, vol. 49, 2009.

David Avis, David Bremner & Antoine Deza (eds.),Polyhedral Computation, vol. 48, 2009.

John Harnad & Pavel Winternitz (eds.), Groups andSymmetries: From Neolithic Scots to John McKay,vol. 47, 2009.

Jean-Marie De Koninck, Andrew Granville & FlorianLuca (eds.), Anatomy of Integers, vol. 46, 2008.

Panos M. Pardalos & Pierre Hansen (eds.), Data Miningand Mathematical Programming, vol. 45, 2008.

Stanley Alama, Lia Bronsard & Peter Sternberg (eds.),Singularities in PDE and the Calculus of Variations,vol. 44, 2007.

Andrew Granville, Melvyn B. Nathanson & JozsefSolymosi (eds.), Additive Combinatorics, vol. 43, 2007.

Donald A. Dawson, Vojkan Jakšić & Boris Vain-berg (eds.), Probability and Mathematical Physics: AVolume in Honor of Stanislav Molchanov, vol. 42, 2007.

André Bandrauk, Michel C. Delfour & ClaudeLe Bris (eds.), High-Dimensional Partial DifferentialEquations in Science and Engineering, vol. 41, 2007.

Vestislav Apostolov, Andrew Dancer, Nigel Hitchin& McKenzie Wang (eds.), Perspectives in Comparison,Generalized and Special Geometry, vol. 40, 2006.

Pavel Winternitz, David Gomez-Ullate, Arieh Iserles,Decio Levi, Peter J. Olver, Reinout Quispel & PiergiulioTempesta (eds.), Group Theory and Numerical Analysis,vol. 39, 2005.

Jacques Hurtubise & Eyal Markman (eds.), AlgebraicStructures and Moduli Spaces, vol. 38, 2004.

Piergiulio Tempesta, Pavel Winternitz, John Harnad,Willard Miller Jr., George Pogosyan & Miguel A. Ro-driguez (eds.), Superintegrability in Classical andQuan-tum Systems, vol. 37, 2004.

Hershy Kisilevsky & Eyal Z. Goren (eds.), Number The-ory, vol. 36, 2004.

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Publications

H. E. A. Eddy Campbell & David L. Wehlau (eds.), In-variant Theory in All Characteristics, vol. 35, 2004.

Pavel Winternitz, John Harnad, C. S. Lam & Jiří Pat-era (eds.), Symmetry in Physics, vol. 34, 2004.

André D. Bandrauk, Michel C. Delfour & ClaudeLe Bris (eds.), Quantum Control: Mathematical and Nu-merical Challenges, vol. 33, 2003.

Vadim B. Kuznetsov (ed.), The Kowalevski Property,vol. 32, 2002.

John Harnad & Alexander R. Its (eds.), IsomonodromicDeformations and Applications in Physics, vol. 31, 2002.

John McKay & Abdellah Sebbar (eds.), Proceedings onMoonshine and Related Topics, vol. 30, 2001.

Alan Coley, Decio Levi, Robert Milson, Colin Rogers &Pavel Winternitz (eds.), Bäcklund and Darboux Trans-formations, vol. 29, 2001.

John C. Taylor (ed.), Topics in Probability and LieGroups: Boundary Theory, vol. 28, 2001.

Israel M. Sigal & Catherine Sulem (eds.), Nonlinear Dy-namics and Renormalization Group, vol. 27, 2001.

John Harnad, Gert Sabidussi & Pavel Winternitz (eds.),Integrable Systems: From Classical to Quantum, vol. 26,2000.

Decio Levi & Orlando Ragnisco (eds.), SIDE III—Symmetry and Integrability of Difference Equations,vol. 25, 2000.

B. Brent Gordon, James D. Lewis, Stefan Müller-Stach,Shuji Saito & Noriko Yui (eds.), The Arithmetic and Ge-ometry of Algebraic Cycles, vol. 24, 2000.

Pierre Hansen & Odile Marcotte (eds.), Graph Colour-ing and Applications, vol. 23, 1999.

Jan Felipe van Diejen & Luc Vinet (eds.), AlgebraicMethods and q-Special Functions, vol. 22, 1999.

Michel Fortin (ed.), Plates and Shells, vol. 21, 1999.

Katie Coughlin (ed.), Semi-Analytic Methods for theNavier–Stokes Equations, vol. 20, 1999.

Rajiv Gupta & Kenneth S. Williams (eds.), Number The-ory, vol. 19, 1999.

Serge Dubuc & Gilles Deslauriers (eds.), Spline Func-tions and the Theory of Wavelets, vol. 18, 1999.

Olga Kharlampovich (ed.), Summer School in GroupTheory in Banff, 1996, vol. 17, 1998.

Alain Vincent (ed.), Numerical Methods in Fluid Me-chanics, vol. 16, 1998.

François Lalonde (ed.), Geometry, Topology and Dy-namics, vol. 15, 1998.

John Harnad & Alex Kasman (eds.), TheBispectral Prob-lem, vol. 14, 1998.

Michel Delfour (ed.), Boundaries, Interfaces and Transi-tions, vol. 13, 1998.

Peter G. Greiner, Victor Ivrii, Luis A. Seco & CatherineSulem (eds.), Partial Differential Equations and theirApplications, vol. 12, 1997.

Luc Vinet (ed.), Advances in Mathematical Sciences:CRM’s 25 Years, vol. 11, 1997.

Donald E. Knuth, Stable Marriage and Its Relation toOther Combinatorial Problems, vol. 10, 1996.

Decio Levi, Luc Vinet & Pavel Winternitz (eds.), Sym-metries and Integrability of Difference Equations, vol. 9,1995.

Joel S. Feldman, Richard Froese & Lon M. Rosen (eds.),Mathematical Quantum Theory II: Schrödinger Opera-tor, vol. 8, 1995.

Joel S. Feldman, Richard Froese & Lon M. Rosen (eds.),Mathematical Quantum Theory I: Field Theory andMany-Body Theory, vol. 7, 1994.

Guido Mislin (ed.), The Hilton Symposium 1993, vol. 6,1994.

Donald A. Dawson (ed.), Measure-Valued Processes,Stochastic Partial Differential Equations and InteractingSystems, vol. 5, 1994.

Hershy Kisilevsky & M. Ram Murty (eds.), EllipticCurves and Related Topics, vol. 4, 1994.

Andrei L. Smirnov & Rémi Vaillancourt (eds.), Asymp-totic Methods in Mechanics, vol. 3, 1993.

Philip D. Loewen, Optimal Control via NonsmoothAnalysis, vol. 2, 1993.

M. Ram Murty (ed.), Theta Functions, vol. 1, 1993.

SpringerCRM Series in Mathematical Physics

André D. Bandrauk & Misha Ivanov (eds.), QuantumDynamic Imaging, 2011.

John Harnad (ed.), Random Matrices, Random Processesand Integrable Systems, 2011.

Marc Thiriet, Biology and Mechanics of Blood Flows,2008 (2 volumes).

David Sénéchal, André-Marie Tremblay & ClaudeBourbonnais (eds.), Theoretical Methods for StronglyCorrelated Electrons, 2003.

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Centre de recherches mathématiqes

*Roman Jackiw, Lectures on Fluid Dynamics, 2002.

Yvan Saint-Aubin & Luc Vinet (eds.), TheoreticalPhysics at the End of the Twentieth Century, 2001.

Yvan Saint-Aubin & Luc Vinet (eds.), Algebraic Meth-ods in Physics, 2000.

Jan Felipe van Diejen & Luc Vinet (eds.), Calogero–Moser–Sutherland Models, 1999.

Robert Conte (ed.), The Painlevé Property, 1999.

Richard MacKenzie, Manu B. Paranjape & Woj-ciech J. M. Zakrzewski (eds.), Solitons, 1999.

Luc Vinet & Gordon Semenoff (eds.), Particles andFields, 1998.

Séminaires de mathématiques supérieures

Vašek Chvátal (ed.), Combinatorial Optimization: Meth-ods and Applications, NATO Science for Peace and Se-curity Series - D: Information and Communication Se-curity, vol. 31, IOS Press, 2011.

Decio Levi, Peter Olver, Zora Thomova & Pavel Win-ternitz (eds.), Symmetries and Integrability of DifferenceEquations, London Mathematical Society Lecture NoteSeries, vol. 381, Cambridge University Press, 2011.

SpringerLecture Notes in Statistics (subseries CRM)

Marc Moore (ed.), Spatial Statistics: Methodological As-pects and Applications, vol. 159, 2001.

S. Ejaz Ahmed & Nancy Reid (eds.), Empirical Bayesand Likelihood Inference, vol. 148, 2001.

Les Publications CRM

Laurent Guieu & Claude Roger, L’Algèbre et le Groupede Virasoro, 2007.

Luc Lapointe, Ge Mo-Lin, Yvan Saint-Aubin & LucVinet, Proceedings of the Canada–China Meeting onTheoretical Physics, 2003.

Armel Mercier, Fonctions de plusieurs variables : Diffé-rentiation, 2002.

Nadia El-Mabrouk, Thomas Lengauer & DavidSankoff (eds.), Currents in Computational MolecularBiology, 2001.

James G. Huard & Kenneth S. Williams (eds.), The Col-lected Papers of Sarvadaman Chowla. Volume I: 1925–1935; Volume II: 1936–1961; Volume III: 1962–1986,2000.

Michael Barr & Charles Wells, Category Theory forComputing Science, 1999.

Maximilian Ya. Antimirov, Andrei A. Kolyshkin &Rémi Vaillancourt, Mathematical Models for Eddy Cur-rent Testing, 1998.

Xavier Fernique, Fonctions aléatoires gaussiennes, vec-teurs aléatoires gaussiens, 1997.

Faqir Khanna & Luc Vinet (eds.), Field Theory, Inte-grable Systems and Symmetries, 1997.

Paul Koosis, Leçons sur le théorème de Beurling et Mal-liavin, 1996.

David W. Rand, Concorder Version Three, 1996 (soft-ware and user guide).

Jacques Gauvin, Theory of Nonconvex Programming,1994.

Decio Levi, Curtis R. Menyuk & Pavel Winter-nitz (eds.), Self-Similarity in Stimulated Raman Scatter-ing, 1994.

Rémi Vaillancourt, Compléments de mathématiquespour ingénieurs, 1993.

Robert P. Langlands & Dinakar Ramakrishnan (eds.),The Zeta Functions of Picard Modular Surfaces, 1992.

Florin N. Diacu, Singularities of the N -Body Problem,1992.

Jacques Gauvin, Théorie de la programmation mathé-matique non convexe, 1992.

Pierre Ferland, Claude Tricot & Axel van de Walle,Analyse fractale, 1992 (software and user guide).

Stéphane Baldo, Introduction à la topologie des en-sembles fractals, 1991.

Robert Bédard, Groupes linéaires algébriques, 1991.

Rudolf Beran & Gilles R. Ducharme, Asymptotic Theoryfor Bootstrap Methods in Statistics, 1991.

James D. Lewis, A Survey of the Hodge Conjecture, 1991.

David W. Rand & Tatiana Patera, Concorder, 1991 (soft-ware and user guide).

David W. Rand & Tatiana Patera, Le Concordeur , 1991(software and user guide).

Véronique Hussin (ed.), Lie Theory, Differential Equa-tions and Representation Theory, 1990.

John Harnad & Jerrold E. Marsden (eds.), HamiltonianSystems, Transformation Groups and Spectral Trans-form Methods, 1990.

M. Ram Murty (ed.), Automorphic Forms and AnalyticNumber Theory, 1990.

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Publications

Wendy G. McKay, Jiří Patera & David W. Rand, Tablesof Representations of Simple Lie Algebras. Volume I: Ex-ceptional Simple Lie Algebras, 1990.

Anthony W. Knapp, Representations of Real ReductiveGroups, 1990.

Wendy G. McKay, Jiří Patera & David W. Rand, Sim-pLie, 1990 (software and user guide).

Francis H. Clarke, Optimization and Nonsmooth Anal-ysis, Montréal, 1989.

Samuel Zaidman, Une Introduction à la théorie des équa-tions aux dérivées partielles, 1989.

*Yuri I. Manin, Quantum Groups and NoncommutativeGeometry, 1988.

Lucien Le Cam, Notes on Asymptotic Methods in Statis-tical Decision Theory, 1974.

Les Presses de l’Université de MontréalChaire Aisenstadt

*Laurent Schwartz, Semimartingales and their Stochas-tic Calculus on Manifolds, 1984.

*Yuval Ne′eman, Symétries, jauges et variétés de groupe,1979.

*R. Tyrrell Rockafellar, La théorie des sous-gradients etses applications à l’optimisation, fonctions convexes etnon convexes, 1979.

*Jacques-Louis Lions, Sur quelques questions d’analyse,de mécanique et de contrôle optimal, 1976.

*Donald E. Knuth, Mariages stables et leurs relationsavec d’autres problèmes combinatoires, 1976.

*Robert Hermann, Physical Aspects of Lie GroupTheory,1974.

*Mark Kac, Quelques problèmes mathématiques en phy-sique statistique, 1974.

*Sybreen de Groot, La transformation de Weyl et lafonction de Wigner : une forme alternative de la méca-nique quantique, 1974.

Other Collaborations with Publishers

Marc Moore, Sorana Froda & Christian Léger (eds.),Mathematical Statistics and Applications: Festschrift forConstance van Eeden, Lecture Notes–Monograph Se-ries, vol. 42, 2003 (a collaboration with the Institute ofMathematical Statistics).

Duong H. Phong, Luc Vinet & Shing-Tung Yau (eds.),Mirror Manifolds and Geometry, AMS/IP Studies in Ad-vanced Mathematics, vol. 10, 1998 (a collaboration withthe AMS and International Press).

Pierre Ferland, Claude Tricot & Axel van de Walle,Fractal Analysis User’s Guide, 1994 (a collaborationwith the AMS).

Hedy Attouch, Jean-Pierre Aubin, Francis Clarke &Ivar Ekeland (eds.), Analyse non linéaire, 1989 (a col-laboration with Gauthier-Villars).

Videos

Efim Zelmanov, Abstract Algebra in the 20th Century,1997.

Serge Lang, Les grands courants, 1991.

Robert Bédard, Brouiller les cartes, 1991.

Serge Lang, Les équations diophantiennes, 1991.

Laurent Schwartz, Le mouvement brownien, 1990.

Laurent Schwartz, Une vie de mathématicien, 1989.

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Scientific Personnel

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Scientific Personnel

CRMMembers in 2012–2013

In contrast with most other mathematics institutes around the world, the CRM can count on the solid foundationof regular, associate, and invited members. Most regular members are also professors at one of the partner in-stitutions: Montréal, Concordia, McGill, UQAM, Laval, Sherbrooke, and Ottawa. Other members are researchersaffiliated with the CRM in 2012–2013 as part of exchange agreements with neighbouring universities and indus-try or are long-term visitors from Canadian and foreign institutions. The presence at the CRM of such an activegroup of researchers has brought many benefits to the Centre. In particular, the national program of the CRM isgreatly facilitated by having on hand a large reserve of willing organizers, who even contribute financially to theorganization of activities. The largest partnership is with the Université de Montréal, which grants the equiva-lent of five full-time teaching positions in release time to the CRM. Release agreements with the other Montréalarea universities afford the equivalent of two more full-time positions to the CRM. Facilities are also providedto researchers affiliated with junior colleges. Several members are affiliated with the CRM through industrialagreements.

Regular members

Louigi Addario-Berry, McGill

Syed Twareque Ali, Concordia

Jean-François Angers, Montréal

Vestislav Apostolov, UQAM

Ibrahim Assem, Sherbrooke

André D. Bandrauk, Sherbrooke

Line Baribeau, Laval

Peter Bartello, McGill

Robert Bédard, UQAM

Jacques Bélair, Montréal

Habib Benali, UPMC & Inserm

Yoshua Bengio, Montréal

François Bergeron, UQAM

Marco Bertola, Concordia

Yves Bourgault, Ottawa

Anne Bourlioux, Montréal

Steven P. Boyer, UQAM

Gilles Brassard, Montréal

Srečko Brlek, UQAM

Thomas Brüstle, Sherbrooke & Bishop’s

Virginie Charette, Sherbrooke

Cédric Chauve, Simon Fraser

Vašek Chvátal, Concordia

Rustum Choksi, McGill

Francis H. Clarke, Lyon 1

Olivier Collin, UQAM

Octav Cornea, Montréal

Miklós Csűrös, Montréal

Chris J. Cummins, Concordia

Galia Dafni, Concordia

Henri Darmon, McGill

Chantal David, Concordia

Jean-Marie De Koninck, Laval

Michel C. Delfour, Montréal

Maxime Descoteaux, Sherbrooke

Eusebius J. Doedel, Concordia

Pierre Duchesne, Montréal

Thierry Duchesne, Laval

Nadia El-Mabrouk, Montréal

André Fortin, Laval

Richard Fournier, Dawson & Montréal

Marlène Frigon, Montréal

André Garon, Polytechnique Montréal

Paul M. Gauthier, Montréal

Christian Genest, McGill

Eyal Z. Goren, McGill

Andrew Granville, Montréal

Christophe Grova, McGill

Alfred Michel Grundland, UQTR

Pengfei Guan, McGill

Geňa Hahn, Montréal

Richard L. Hall, Concordia

Sylvie Hamel, Montréal

John Harnad, Concordia

Tony R. Humphries, McGill

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Centre de recherches mathématiqes

Jacques Hurtubise, McGill

Véronique Hussin, Montréal

Adrian Iovita, Concordia

Dmitry Jakobson, McGill

Vojkan Jakšić, McGill

Tomasz Kaczynski, Sherbrooke

Niky Kamran, McGill

Olga Kharlampovich, McGill

Hershy Kisilevsky, Concordia

Paul Koosis, McGill

Dmitry Korotkin, Concordia

Gilbert Labelle, UQAM

John Labute, McGill

Matilde Lalín, Montréal

François Lalonde, Montréal

Benoît Larose, Champlain St-Lambert & Concordia

Michael Lau, Laval

Christian Léger, Montréal

Frédéric Lesage, Polytechnique Montréal

Jean-Philippe Lessard, Laval

Sabin Lessard, Montréal

Claude Levesque, Laval

Jean-Marc Lina, ÉTS

Shiping Liu, Sherbrooke

Emmanuel Lorin de la Grandmaison, Carleton

Steven Lu, UQAM

Brenda MacGibbon, UQAM

Michael C. Mackey, McGill

Vladimir Makarenkov, UQAM

Michael Makkai, McGill

Javad Mashreghi, Laval

Sherwin A. Maslowe, McGill

Pierre Mathieu, Laval

John McKay, Concordia

Manuel Morales, Montréal

M. Ram Murty, Queen’s

Fahima Nekka, Montréal

Adam M. Oberman, McGill

Robert G. Owens, Montréal

Manu Paranjape, Montréal

Jiří Patera, Montréal

François Perron, Montréal

Mikaël Pichot, McGill

Iosif Polterovich, Montréal

Lea Popovic, Concordia

James O. Ramsay, McGill

Thomas J. Ransford, Laval

Bruno Rémillard, HEC Montréal

Christophe Reutenauer, UQAM

Louis-Paul Rivest, Laval

Frédéric Rochon, UQAM

Ivo G. Rosenberg, Montréal

Christiane Rousseau, Montréal

Damien Roy, Ottawa

Peter Russell, McGill

Yvan Saint-Aubin, Montréal

David Sankoff, Ottawa

Dana Schlomiuk, Montréal

Robert Seiringer, McGill

Alexander Shnirelman, Concordia

Vasilisa Shramchenko, Sherbrooke

Alina Stancu, Concordia

Ron J. Stern, Concordia

Alain Tapp, Montréal

Francisco Thaine, Concordia

John A. Toth, McGill

Lennaert van Veen, UOIT

Roger Villemaire, UQAM

Luc Vinet, Montréal

Johannes Walcher, McGill

Timothy R. S. Walsh, UQAM

Pavel Winternitz, Montréal

Daniel T. Wise, McGill

Xiaowen Zhou, Concordia

Associate members

Nantel Bergeron, York

Robert Conte, CEA/Saclay

Stéphane Durand, Édouard-Montpetit

Bertrand Eynard, CEA/Saclay

Martin J. Gander, Genève

Pierre Ille, CNRS & Aix-Marseille

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Scientific Personnel

Marc Laforest, Polytechnique Montréal

Decio Levi, Roma Tre

Jun Li, Pharsight

Emmanuel Lorin de la Grandmaison, Carleton

Yiannis N. Petridis, Univ. Coll. London

Elisa Shahbazian, OODA Technologies

Marc Thiriet, CNRS, UPMC & INRIA Rocquencourt

Pierre Valin, Defence R&D Canada

Carolyne M. Van Vliet, Montréal & Miami

Jean-Paul Zolésio, INRIA Sophia Antipolis

Invited members

Mylène Bédard, Montréal

Louis G. Doray, Montréal

Laurent Habsieger, CNRS & Lyon 1

Pierre Lafaye de Micheaux, Montréal

Sheila Sandon, Nantes

Yuanli Zhang

Postdoctoral Fellows

Each year the CRM plays host to a large number of postdoctoral fellows. Their funding is provided through theNSERC and FRQNT postdoctoral programs, a NATO international program administered by NSERC, the CRM(usually in collaboration with the ISM), the CRM research laboratories, and individual research grants from CRMmembers. The list below includes postdoctoral fellows in residence at the CRM and those cofunded by the CRM.Some of the fellows were in residence at the CRM for only part of the year. The affiliation given is the institutionwhere the doctorate was obtained.

Elif Fidan Acar, Toronto

Shabnam Akhtari, UBC

Ferenc Balogh, Concordia

Jessica Banks, Oxford

Sandro Bettin, Bristol

Alexander Bihlo, Wien

Cameron Brown, Florida

Renato Calleja, UT Austin

Vorrapan Chandee, Stanford

Adam Clay, UBC

Tiago Dinis da Fonseca, UPMC

Fabrizio Donzelli, Miami

Abdelkrim El Basraoui, Ottawa

Suresh Eswarathasan, Rochester

Renjie Feng, Northwestern

François Fillion-Gourdeau, McGill

Ke Gong, Henan

Philip Grech, ETH Zürich

Melita Hadzagic, McGill

Mariah E. Hamel, UBC

Adam J. Harper, Cambridge

Azadeh Jafari, EPFL

Gwenaël Joret, ULB

Nabil Kahouadji, Paris Diderot

Caroline Kalla, Bourgogne

Abdoulaye Sabou Kane, Laval

Ilya Karzhemanov, Edinburgh

Leila Kheibarshekan, Gent

Dmitry Kolomenskiy, Provence

Dimitris Koukoulopoulos, UI Urbana-Champaign

Eunghyun Lee, UC Davis

Antonio Lei, Cambridge

Alejandro Morales, MIT

Guyslain Naves, Joseph Fourier

Sarah Post, Minnesota

Stamatis Pouliasis, Aristotle

Danilo Riglioni, Roma Tre

Vivien Ripoll, Paris Diderot

Matthew Roberts, Bath

Mathew D. Rogers, UBC

Yakov Savelyev, Stony Brook

Jihye Seo, Harvard

Egor Shelukhin, Tel Aviv

David Sher, Stanford

Ethan C. Smith, Clemson

Marzena Szajewska, Bialystok

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Centre de recherches mathématiqes

Agnieszka Tereszkiewicz, Bialystok

Carl Tipler, Nantes

Ihsan Ata Topaloglu, IU Bloomington

Pascal Turbis, Montréal

Matthias Westrich, Aarhus

Mark Wilde, Southern California

Driss Yacoubi, UPMC

Guofu Yu, Shanghai Jiao Tong

Yuxiang Zhang, Memorial

Visitors

Each year the CRM hosts a large number of visitors. The majority come to the Centre to participate in scientificactivities organized or co-organized by the CRM. In 2012–2013 there were 10 activities in the thematic programand 557 researchers took part in these activities, 9 of which were held at the CRM itself. There were also 14activities in the general program, 7 of which were held at the CRM; altogether 386 participants took part in theseactivities. Finally the multidisciplinary and industrial program featured 2 activities, one of which took place atthe CRM; 58 researchers participated in the activity held at the CRM.

Long-term visitors

The following list only includes visitors who were inresidence for at least four weeks.

Mattia Cafasso, Angers

Pierre Cagne, ÉNS

Chi-Yun Chuang, NTHU

Vladimir Dorodnitsyn, Keldysh Inst.

Gerard Freixas i Montplet, Paris Diderot

Alexandre Girouard, Neuchâtel

Elisa Gouvea Mauricio Ferreira, McGill

Jiří Hrivnák, TU Prague

Azadeh Jafari, Cardiff

Can Kozcaz, SISSA

Decio Levi, Roma Tre

Xiannan Li, UI Urbana-Champaign

Chunshan Lin, Tokyo

Frithjof Lutscher, Ottawa

Keivan Mallahi Karai, Jacobs

Luigi Martina, Salento

Alexi Morin-Duchesne, Montréal

Aïda Ouangraoua, Simon Fraser

Lucas Pastor, Savoie

Claude-Alain Pillet, Toulon

Raphaël Ponge, Seoul NU

Maksym Radziwill, Stanford

Libor Šnobl, TU Prague

Aleksander Strasburger, SGGW

Michael Sullivan, UMass Amherst

Marc Thiriet, UPMC

Zora Thomova, SUNY IT

Nicolae Vulpe, IMI Moldova

Oleksiy Zhedanov, Donetsk IPE

Wadim Zudilin, Newcastle, AU

Short-term visitors

The following visitors were in residence for less thanfour weeks.

Sergei Agafonov, João Pessoa

Silvia Anjos, IST

Joan Carles Artés, UA Barcelona

Alain Aspect, Inst. d’Optique

Ferenc Balogh, SISSA

Ram Band, Bristol

Jonathan Bober, Washington

Alina Bucur, UC San Diego

Goce Chadzitaskos, Doppler Inst.

Edmund Yik-Man Chiang, Hong Kong UST

Matthias Christandl, ETH Zürich

Robert Conte, CEA/Saclay

Charles Doran, Alberta

Anton Dzhamay, Northern Colorado

Paul D. Embrechts, ETH Zürich

Mauricio Adrian Escobar Ruiz, UNAM

Brooke Feigon, East Anglia

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Scientific Personnel

Rupert L. Frank, Princeton

Jürg Fröhlich, ETH Zürich

Leo Goldmakher, Toronto

María del Mar González Nogueras, UPC

Emir Gumrukcuoglu, Tokyo

Thomas Hoffmann-Ostenhof, Wien

Nail H. Ibragimov, Blekinge IT

Mourad E. H. Ismail, Central Florida

Alexander R. Its, IUPUI

Caroline Kalla, Orléans

Mikhail Karpukhin, Moscow SU

Takeshi Kobayashi, Toronto

Nam Le, Courant Inst.

Yi-Jen Lee, Chinese U Hong Kong

Frank Lemire, Windsor

Michael Levitin, Reading

Xiannan Li, UI Urbana-Champaign

Elijah Liflyand, Bar-Ilan

Jérôme Martin, IAP

Hiroshi Miki, Kyoto

Micah B. Milinovich, Mississippi

Willard Miller Jr., Minnesota

Robert V. Moody, Alberta

Emmy Murphy, MIT

Aleksander Yu. Orlov, Shirshov Inst.

Milena Pabiniak, Toronto

Leonid Parnovski, Univ. Coll. London

Subodh Patil, ÉNS

Alexei V. Penskoi, Moscow SU

Patrick Peter, IAP

Anne-Charlotte Philippe, INRIA Sophia Antipolis

Martin Pinsonnault, Western Ontario

Sarah Post, UH Mānoa

Vincent Rivasseau, Paris-Sud

Jeremy Rouse, Wake Forest

Jimena Royo-Letelier, Paris-Dauphine

Philippe Ruelle, UC Louvain

Detchat Samart, Texas A&M

Emmanuel Schertzer, UPMC

Wil H. A. Schilders, TU Eindhoven

Kai Schneider, TU Kaiserslautern

Chunhua Shan, York

Suzanne Shontz, Mississippi SU

Nadia Sidorova, Univ. Coll. London

Mark Siggers, Kyungpook NU

Philippe Sosoe, Princeton

PhanThanh Nam, Cergy-Pontoise

Alexander Turbiner, UNAM

Daniel Ueltschi, Warwick

Vincent Vennin, IAP

Mark A. Walton, Lethbridge

Daqing Wan, UC Irvine

Simone Warzel, TU München

Hongmei Zhu, York

Peter Zograf, Steklov Inst.

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List of Students Having Graduated in2012–2013

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List of Students Having Graduated in 2012–2013

The CRM members supervise a large number of graduate students. In this section we give information on thestudents supervised by CRM members who graduated in 2012–2013. The name of the student is followed

by the name of his or her supervisor (or names of his or her supervisors), his or her institution, and his or herprogram. Some names may be missing from this list, because we have only included those that have been broughtto our attention.

Ph.D. Students

Isabelle Ascah-CoallierAbraham BroerUniversité de MontréalMathematics (pure mathematics option)

Mohammad BardestaniAndrew GranvilleUniversité de MontréalMathematics (pure mathematics option)

Zied Ben SalahLouis G. Doray; Manuel MoralesUniversité de MontréalMathematics (applied mathematics option)

Erwan BilandClaude LevesqueUniversité LavalMathematics

Richard BoisAndré Fortin; Michel FortinUniversité LavalMathematics

Yaiza CanzaniDmitry JakobsonMcGill UniversityMathematics

Francesc CastellaHenri DarmonMcGill UniversityMathematics

Zhuge ChanjingMichael C. MackeyMcGill UniversityPhysiology

François CharestFrançois Lalonde; Octav CorneaUniversité de MontréalMathematics (pure mathematics option)

François CharetteOctav CorneaUniversité de MontréalMathematics (pure mathematics option)

Thierry Chekouo TekougangAlejandro MuruaUniversité de MontréalStatistics

Mohammad Hossein DehghanThierry DuchesneUniversité LavalStatistics

Olivier DelalleauYoshua BengioUniversité de MontréalComputer science

Alpha Boubacar DialloVladimir MakarenkovUniversité du Québec à MontréalComputer science

Plamen DragievVladimir MakarenkovUniversité du Québec à MontréalComputer science

Peyman EslamiPawel Gora; Abraham BoyarskyConcordia UniversityMathematics

Yasser FarhatFrédéric Gourdeau; Thomas J. RansfordUniversité LavalMathematics

Ionica Groparu-CojocaruLouis G. Doray; Manuel MoralesUniversité de MontréalMathematics (applied mathematics option)

Lenka HákováJiří PateraUniversité de MontréalMathematics (applied mathematics option)

Salima HassaineYann-Gaël Guéhéneuc; Sylvie HamelUniversité de MontréalComputer science

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Centre de recherches mathématiqes

Charles HélouGilles BrassardUniversité de MontréalComputer science

Kassem KalachGilles Brassard; Louis SalvailUniversité de MontréalComputer science

Johanna KaroubyRobert BrandenbergerMcGill UniversityPhysics

Hamid KhakdamanYves Bourgault; Marten TernanUniversity of OttawaChemical Engineering

Hussein KhreibaniVasilisa ShramchenkoUniversité de SherbrookeMathematics

Michelle LaroucheJiří PateraUniversité de MontréalMathematics (applied mathematics option)

Nima LashkariAlexander Maloney; Patrick HaydenMcGill UniversityMathematics

Mehdi LayeghifardVladimir MakarenkovUniversité du Québec à MontréalBiology

Adrien LemaitreGena Hahn; Benoît LaroseUniversité de MontréalComputer science

Hui Li LiuXiaowen ZhouConcordia UniversityStatistics

Amanollah MehrabianDavid A. StephensMcGill UniversityStatistics

Alexi Morin-DuchesneYvan Saint-AubinUniversité de MontréalPhysics

Mohammad Najafi IvakiAlina StancuConcordia UniversityMathematics

Guillaume ProvencherYvan Saint-AubinUniversité de MontréalPhysics

Yassir RabhiMasoud Asgharian; Brenda MacGibbonMcGill UniversityStatistics

Hela RomdhaniLajmi Lakhal-Chaieb; Louis-Paul RivestUniversité LavalStatistics

Olivier RouchMadrane Aziz; Paul ArminjonUniversité de MontréalMathematics (applied mathematics option)

Mireille SchnitzerErica E. M. MoodieMcGill UniversityBiostatistics

Narinder SharmaDominic Rochon; Kuldeep S. CharakUniversité du Québec à Trois-RivièresMathematics

Karine St-OngeFrançois Major; Sylvie HamelUniversité de MontréalComputer science

Bocar Amadou WaneJosé Manuel Urquiza; André FortinUniversité LavalMathematics

Alisha WissanjiAlexander Maloney; Keshav DasguptaUniversité de MontréalPhysics

Yongling XiaoErica E. M. Moodie; Michal AbrahamowiczMcGill UniversityBiostatistics

Wei XueRobert BrandenbergerMcGill UniversityPhysics

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List of Students Having Graduated in 2012–2013

M.Sc. Students

Albert AjonkeuLouis-Paul RivestUniversité LavalStatistics

Farid AoujiLajmi Lakhal-Chaieb; Belkacem AbdousUniversité LavalMathematics

Samuel AprilLouis-Paul ArguinUniversité de MontréalMathematics (applied mathematics option)

Farzad AryanAndrew GranvilleUniversité de MontréalMathematics (pure mathematics option)

Adétona O. Paterne BadaLouis-Paul RivestUniversité LavalStatistics

Nadia BahriQazi Ibadur RahmanUniversité de MontréalMathematics (pure mathematics option)

Jean-François BéginMylène Bédard; Patrice GaillardetzUniversité de MontréalMathematics (applied mathematics option)

Latifa Ben Hadj SlimeneÉric MarchandUniversité de SherbrookeMathematics

Fabiola Bene TchaleuDavid Haziza; Pierre DuchesneUniversité de MontréalStatistics

Ryan BentyAlina StancuConcordia UniversityMathematics

Francesca BergamaschiAdrian IovitaConcordia UniversityMathematics

Thanina BerkaneChristian Léger; Piere DuchesneUniversité de MontréalStatistics

Valentin BissonYoshua BengioUniversité de MontréalComputer science

Timothy BlaisAlexander MaloneyMcGill UniversityMathematics

Éloïse BoiteauAndré FortinUniversité LavalMathematics

Samuel BoucherVestislav ApostolovUniversité du Québec à MontréalMathematics

Catalina ButnariuDavid HazizaUniversité de MontréalStatistics

Hassan ChoueibMichel C. DelfourUniversité de MontréalMathematics (applied mathematics option)

Paul Robert ChouhaAlain Tapp; Gilles BrassardUniversité de MontréalComputer science

Maurice-Étienne CloutierJean-Marie De Koninck; Claude LevesqueUniversité LavalMathematics

Marc-Alexandre CôtéShengrui Wang; Maxime DescoteauxUniversité de SherbrookeMathematics

Bianca Côté-BrunetJean-François Angers; Manuel MoralesUniversité de MontréalStatistics

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Centre de recherches mathématiqes

Miguel Alfredo Cutimanco PanduroVirginie Charette; Vasilisa ShramchenkoUniversité de SherbrookeMathematics

Pierre-Luc CyrJean-François AngersUniversité de MontréalStatistics

Philippe DelormePierre Lafaye de MicheauxUniversité de MontréalStatistics

Marie-Hélène DescaryFabrice LarribeUniversité du Québec à MontréalMathematics (statistics option)

Caroline DeschênesChristian LégerUniversité de MontréalStatistics

Jean-François DésiletsPavel WinternitzUniversité de MontréalPhysics

Hugo Drouin-VaillancourtAlain TappUniversité de MontréalComputer science

Yeting DuAbbas Khalili; Johanna NešlehováMcGill UniversityStatistics

Mathieu DupontFabrice LarribeUniversité du Québec à MontréalMathematics (statistics option)

David ÉmondNadia GhazzaliUniversité LavalMathematics

Laura C. Eslava FernándezLouigi Addario-BerryMcGill UniversityMathematics

Andrew FenwickGalia DafniConcordia UniversityMathematics

Heinz FiedlerAlain TappUniversité de MontréalComputer science

Iulian FransinescuRené FerlandUniversité du Québec à MontréalMathematics

Alexandre FréchetteBruce ShepherdMcGill UniversityMathematics

Yves GagnonNadia El-MabroukUniversité de MontréalBioinformatics

Ludovick GagnonJosé Manuel UrquizaUniversité LavalMathematics

Shan GaoAdrian IovitaConcordia UniversityMathematics

Gabriel GirardMaxime DescoteauxUniversité de SherbrookeMathematics

Mireille GuerrierLouis-Paul RivestUniversité LavalStatistics

Dezhao HanJosé GarridoConcordia UniversityActuarial science

Julie HérouxErica E. M. MoodieMcGill UniversityBiostatistics

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List of Students Having Graduated in 2012–2013

Eliot HijanoAlexander MaloneyMcGill UniversityMathematics

Zahraa IssaMatilde LalínUniversité de MontréalMathematics (pure mathematics option)

Samuel JohnsonMarni MishnaSimon Fraser UniversityMathematics

Philip LagogianisAlexander MaloneyMcGill UniversityMathematics

Sandra LarrivéeJean-François RenaudUniversité du Québec à MontréalMathematics

Jean-Sébastien LechasseurMatilde LalinUniversité de MontréalMathematics (pure mathematics option)

Jean-Sébastien LévesqueRobert GuénetteUniversité LavalMathematics

Erin LundyDavid B. Wolfson; David A. StephensMcGill UniversityStatistics

Dominique MaheuxRobert GuénetteUniversité LavalMathematics

Céline MaistretHershy Kisilevsky; Adrian IovitaConcordia UniversityMathematics

Viktor MarushkaIosif PolterovichUniversité de MontréalMathematics (pure mathematics option)

Jérémie MathieuDominic Rochon; Louis MarchildonUniversité du Québec à Trois-RivièresPhysics

Annaliza McGillivrayAbbas KhaliliMcGill UniversityStatistics

Nassim MojaverianErica E. M. MoodieMcGill UniversityBiostatistics

Marcela MolinieJacques BélairUniversité de MontréalMathematics (applied mathematics option)

Vanessa W. K. NgFrédéric LesageÉcole Polytechnique de MontréalElectrical Engineering

Jean-François NoletVirginie CharetteUniversité de SherbrookeMathematics

Ivo PendevPawel GoraConcordia UniversityMathematics

David Olivier PhamManuel MoralesUniversité de MontréalStatistics

Marta PieropanAdrian IovitaConcordia UniversityMathematics

Dany PilonMathieu BoudreaultUniversité du Québec à MontréalMathematics (financial mathematics option)

Alan RegisWei SunConcordia UniversityStatistics

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Centre de recherches mathématiqes

Reza SadoughianzadehAdrian IovitaConcordia UniversityMathematics

Becem SaidaniÉric Marchand; Maxime DescoteauxUniversité de SherbrookeMathematics

Etienne Saint-AmantMaxime DescoteauxUniversité de SherbrookeMathematics

Modou SeneThierry DuchesneUniversité LavalStatistics

David SimonyanThierry DuchesneUniversité LavalStatistics

Kevin SookheeWei SunConcordia UniversityStatistics

Dong SunYogendra P. ChaubeyConcordia UniversityStatistics

Yasmine TawfikRobert G. OwensUniversité de MontréalMathematics (applied mathematics option)

Hervé Tchouake TchuiguepFrançois PerronUniversité de MontréalStatistics

TommyThomassinGeneviève Gauthier; Mathieu BoudreaultHEC MontréalFinancial Engineering

Marie-Hélène ToupinLouis-Paul RivestUniversité LavalStatistics

Hugo TremblayGilbert LabelleUniversité du Québec à MontréalMathematics

Véronique TremblayAnne-Catherine Favre; Thierry DuchesneUniversité LavalStatistics

Benoit TricotMaxime DescoteauxUniversité de SherbrookeMathematics

Loukia TsakanikasLennaert van Veen; Eusebius DoedelConcordia UniversityMathematics

Jean-Philippe TurcotteÉric MarchandUniversité de SherbrookeMathematics

Fan ZhangYogendra P. ChaubeyConcordia UniversityStatistics

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Governance and Scientific Guidance

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Centre de recherches mathématiqes

The CRM structure consists of a Board of Directors, an Assembly of Members, an International Scientific Ad-visory Committee, a Local Scientific Committee, an Executive Committee, and a Committee of Directors

of Laboratories. In 2012–2013 the members of the Local Scientific Committee were Christian Genest (McGillUniversity), Andrew Granville (Université de Montréal), Dmitry Jakobson (McGill University), François Lalonde(Université de Montréal; Director of the CRM), and Lea Popovic (Concordia University). The Executive Committeeconsists of the CRM Director and the Deputy Directors. For more information, the reader may consult the website crm.math.ca/apropos/CRM_structure_an.shtml.

Board of DirectorsThe Board of Directors is composed of:

• The Director (ex officio);• A member of the Executive Committee nominated

by the Board for a two-year mandate;• Two regular members nominated by the Assembly

for three-year mandates, normally renewable once;• A Laboratory Director, nominated by the Committee

of Directors of Laboratories for a two-year mandate,normally renewable once;

• The Vice-Principal, Research, of each of the mainpartner universities of the CRM, or his representa-tive;

• A Vice-Principal, Research, of one of the other part-ner universities of the CRM, chosen by these univer-sities on a rotating basis for a two-year mandate.

Here are the members of the Board of Directors for 2012–2013.

Sophie D’Amours, Vice-Rector (Research)Université LavalGraham Carr, Vice-President (Research)Concordia University

Christian GenestMcGill UniversityJacques HurtubiseVice-Principal (Research) RepresentativeMcGill UniversityJohn HarnadConcordia University

François Lalonde, Director of the CRMUniversité de MontréalOdile Marcotte, Deputy Director of the CRMUniversité du Québec à MontréalYves Mauffette, Vice-Rector (Research)Université du Québec à MontréalChristiane RousseauUniversité de MontréalGeneviève Tanguay, Vice-Rector (Research)Université de Montréal

Chantal David (Concordia University) and Octav Cornea (Université de Montréal), Deputy Directors of theCRM, were invited members.

Committee of Directors of Laboratories

The Committee of Directors of Laboratories is composed of the Director, the Directors of the nine CRM Labora-tories and the Deputy Directors of the Centre. It meets at least once a year to discuss any question that concernsthe laboratories. The Directors of the laboratories are:

François Bergeron (UQAM)LaCIM — Combinatorics and Theoretical ComputerScienceSteven P. Boyer (UQAM)CIRGET — Geometry and Topology

Henri Darmon (McGill University)CICMA — Number Theory and AlgebraAndré Fortin (Université Laval)GIREF — Modelling and Numerical SimulationChristian Genest (McGill University)Statistics

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Governance and Scientific Guidance

John Harnad (Concordia University)Mathematical PhysicsDmitry Jakobson (McGill University)Mathematical AnalysisJean-Marc Lina (École de technologie supérieure)PhysNum — Medical Imaging and Pharmacometrics

Adam M. Oberman (McGill University)Applied Mathematics (from January 8th, 2013)Robert G. Owens (Université de Montréal)Applied Mathematics (until January 7th, 2013)

International Scientific Advisory Committee

The International Scientific Advisory Committee consists of distinguished researchers from Canada and abroad.Its members are either mathematicians or scientists with close ties to the mathematical sciences. The AdvisoryCommittee is kept informed regularly of the activities of the Centre through the Director. The Committee makesrecommendations about the general scientific orientations of the CRM and gives advice about proposed scientificactivities.

Martin Barlow received his un-dergraduate degree from the Uni-versity of Cambridge in 1975 andcompleted his doctoral degree withDavid Williams at the UniversityCollege of Swansea in Wales (1978).Since then he has been a leadingresearcher in probability theory, in

particular diffusion in fractals and other disorderedmedia. He held a Royal Society University ResearchFellowship at the University of Cambridge from 1985to 1992, when he joined the Mathematics Departmentat the University of British Columbia. He is currentlyProfessor of Mathematics at UBC. He has held a num-ber of visiting professorships at leading universities.Martin Barlow gave an invited lecture at the 1990 ICMin Kyoto and was an invited lecturer at the presti-gious Saint-Flour Summer School in 1995. In 2008 hereceived the Jeffery-Williams Prize of the CanadianMathematical Society and in 2009 the CRM –Fields–PIMS Prize. Other distinctions include the Rollo David-son Prize from the University of Cambridge and theJunior Whitehead Prize from the London Mathemati-cal Society. He has been a leader of the internationalprobability community as a lead organizer of numer-ous conferences, Associate Editor of all the top prob-ability journals, and Editor-in-Chief of the ElectronicCommunications in Probability. He has been a Fellowof the Institute of Mathematical Statistics since 1995and of the Royal Society of Canada since 1998. In 2006he was elected Fellow of the Royal Society (London).

A specialist of probability the-ory and its applications, GérardBen Arous arrived to the CourantInstitute (NYU) as a Professor ofMathematics in 2002. He was ap-pointed Director of the Courant In-stitute and Vice Provost for Scienceand Engineering Development in

September 2011. A native of France, Professor BenArous studied Mathematics at the École normale su-périeure and earned his Ph.D. from the Université Pa-ris Diderot (1981). He has been a Professor at the Uni-versité Paris-Sud, at the École normale supérieure, andmore recently at the École Polytechnique Fédérale deLausanne, where he held the Chair of Stochastic Mod-elling. He was Chair of the Department of Mathemat-ics at the Université Paris-Sud and the Departments ofMathematics and Computer Science at the École nor-male supérieure. He also founded a Mathematics Re-search Institute in Lausanne, the Bernoulli Center. Heis the managing editor (with Amir Dembo, Stanford) ofone of the main journals in his field, Probability Theoryand Related Fields.

Professor Ben Arous works on probability theory(stochastic analysis, large deviations, random mediaand random matrices) and its connections with otherdomains of mathematics (partial differential equations,dynamical systems), physics (statistical mechanics ofdisordered media), and industrial applications. He ismainly interested in the time evolution of complex sys-tems and the universal aspects of their long-time be-haviour and of their slow relaxation to equilibrium,in particular how complexity and disorder imply ag-ing. He is a Fellow of the Institute of Mathematical

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Centre de recherches mathématiqes

Statistics (as of August 2011) and an elected member ofthe International Statistical Institute. He was a plenaryspeaker at the European Congress of Mathematics, aninvited speaker at the International Congress of Math-ematicians, received a senior Lady Davis Fellowship(Israel), the Rollo Davidson Prize (Imperial College,London), and the Montyon Prize (French Academy ofSciences).

Allan Borodin received his B.A. inMathematics in 1963 (from RutgersUniversity), his M.Sc. in ElectricalEngineering and Computer Sciencein 1966 (from Stevens Institute ofTechnology), and his Ph.D. in Com-puter Science in 1969 (from CornellUniversity). He was a systems pro-

grammer at Bell Laboratories in New Jersey from 1963to 1966 and a Research Fellow at Cornell from 1966to 1969. Since 1969, he has been a professor in theDepartment of Computer Science at the University ofToronto, where he became a full professor in 1977.He was department chair from 1980 to 1985. ProfessorBorodin is a world leader in the mathematical founda-tions of computer science and has made fundamentalcontributions to many areas, including algebraic com-putations, resource tradeoffs, routing in interconnec-tion networks, parallel algorithms, on-line algorithms,and adversarial queuing theory. Professor Borodin hasbeen the editor of many journals, including the SIAMJournal on Computing. He has held positions on, orbeen active in, dozens of committees and organiza-tions, both inside and outside the University, and hasheld several visiting professorships internationally. In1991 Professor Borodin was elected a Fellow of theRoyal Society of Canada and in 2008 he received theCRM –Fields–PIMS Prize.

Stephen E. Fienberg is Mau-rice Falk University Professor ofStatistics and Social Science atCarnegie Mellon University. He isthe Carnegie Mellon codirector ofthe Living Analytics Research Cen-tre. Fienberg received his hon. B.Sc.in Mathematics and Statistics from

the University of Toronto (1964) and his A.M. and Ph.D.degrees in Statistics from Harvard University (1965,1968).

Professor Fienberg has served as Dean of the Collegeof Humanities and Social Sciences at Carnegie Mellon

and as Vice President for Academic Affairs at York Uni-versity, in Toronto, as well as on the faculties of theUniversity of Chicago and the University of Minnesota.He has been a founding editor of a number of statisticaljournals. He has been Vice President of the AmericanStatistical Association and President of the Institute ofMathematical Statistics and the International Societyfor Bayesian Analysis.

Fienberg’s research includes the development of statis-tical methods, especially tools for categorical data anal-ysis and the analysis of network data, algebraic statis-tics, causal inference, statistics and the law, machinelearning, and the history of statistics.

Fienberg is a member of the U.S. National Academy ofSciences, and a fellow of the Royal Society of Canada,the American Academy of Arts and Sciences, and theAmerican Academy of Political and Social Science, aswell as a fellow of the American Association for theAdvancement of Science, the American Statistical As-sociation, the Institute of Mathematical Statistics, andan elected member of the International Statistical In-stitute.

Edward Frenkel grew up in Rus-sia and then moved to the US. Hereceived his Ph.D. in Mathemat-ics from Harvard University at theage of 23 after one year of study.He stayed on at Harvard, first asa Junior Fellow at the prestigiousHarvard Society of Fellows, and

then as an Associate Professor. He was offered a FullProfessorship at the University of California, Berkeleyat the age of 28 (one of the youngest ever), and he hasbeen Professor of Mathematics at Berkeley since then.In 2008 he received the first Chaire d’Excellence awardfrom the Fondation Sciences Mathématiques de Paris.

Frenkel has authored two books and about 80 articlesin mathematical journals, and he has lectured on hiswork around the world. Among his other awards arethe Hermann Weyl Prize and the Packard Fellowshipin Science and Engineering.

Susan Friedlander is currentlyDirector of the Center for AppliedMathematical Sciences and Pro-fessor of Mathematics at the Uni-versity of Southern California. Sheobtained her Doctoral degree atPrinceton University in 1972. She

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Governance and Scientific Guidance

has published extensively in the areas of differentialequations and fluid mechanics. She has been very ac-tive on numerous committees and evaluation panels,including the Council of the American MathematicalSociety and the Board on Mathematical Sciences andTheir Applications of the National Academies. She hasalso been involved continuously in the organizationof conferences and workshops; in particular she wasa member of the AMS-Shanghai Joint Meeting Pro-gram Committee. She has served on numerous AMSeditorial boards and university committees. She hasbeen honoured with several academic awards, includ-ing the Institut Henri-Poincaré Medal, the Gauthier-Villars Prize for Nonlinear Analysis, and the Univer-sity of Illinois Scholar Award (in 2003). Over the years,she has been a frequent invited lecturer in the UnitedStates and around the world.

Mark Goresky has been a memberof the Institute for Advanced Study inPrinceton since 1994. He received hisB.Sc. from the University of BritishColumbia in 1971 and a Ph.D. fromBrown University in 1976. In 1986 hewas elected to the Royal Society ofCanada. He was awarded the Jeffery-

Williams Prize of the Canadian Mathematical Societyin 1996 and the Steele Prize of the American Mathe-matical Society in 2002 (jointly with R. MacPherson).He was a member of the editorial board of the Cana-dian Journal of Mathematics from 1997 to 2000 and iscurrently a member of the editorial board of the Bul-letin of the American Mathematical Society. He is aworld expert in geometric representation theory.

Mark L. Green has been a pro-fessor in the UCLA Departmentof Mathematics since 1982. He re-ceived his Ph.D. from PrincetonUniversity in 1972 and was Direc-tor of the Institute for Pure andApplied Mathematics from 2001 to2008. Mark Green has received nu-

merous honours during his career. In particular, hewas an invited speaker at the International Congressof Mathematicians in Berlin in 1998. He was a plenaryspeaker at the Abel Centennial held in Oslo in 2002and the Hodge Centennial held in Edinburgh in 2003.Professor Green’s services to the mathematical com-munity are extensive. He was a member of the Boardof Trustees at the Claremont Center for the Mathemat-

ical Sciences and a member of the Board of Directorsof the Center for Mathematics and Teaching. Profes-sor Green also served on the NSERC Major ResourcesSupport Committee and was the editor of the Journalof Algebraic Geometry. His research interests are incommutative algebra, algebraic geometry, and appliedmathematics.

Laurent Habsieger has been a se-nior researcher at the Centre na-tional de la recherche scientifique(CNRS) since 2002. A former studentat the École Normale Supérieure(ENS), he completed his Ph.D. inStrasbourg before spending one yearat the IMA (Minneapolis) as a post-

doctoral fellow. He was then a professor at the Univer-sité du Québec à Montréal (UQAM) for two years. In1990 he joined the CNRS as a junior researcher in Bor-deaux and in 2002 he accepted a position as senior re-searcher in Lyon. Laurent Habsieger then managed thenational research group in number theory for 8 years.He was deputy director of his laboratory for 5 yearsand supervised three Franco-Hungarian research pro-grams. In 2011 the CNRS launched the UMI CRM andhe was appointed co-director of the UMI with FrançoisLalonde, director of the CRM.

Having completed his thesis in combinatorics, LaurentHabsieger broadened its expertise to number theory.He is the author of around 40 scientific articles in manyareas of mathematics: combinatorics, arithmetic, spe-cial functions, coding theory, analysis, etc.

Barbara Lee Keyfitz has been aprofessor at the Ohio State Univer-sity since January 2009. She servedas Director of the Fields Institutefor Research in Mathematical Sci-ences from 2004 to 2008. From 2000to 2008, she was John and RebeccaMoores Professor of Mathematics at

the University of Houston, which she joined in 1987,following appointments at Columbia, Princeton, andArizona State University. She studied at the Universityof Toronto and obtained her Ph.D. at the Courant In-stitute (NYU). Barbara Keyfitz is a Fellow of the Amer-ican Association for the Advancement of Science andthe recipient of the 2005 Krieger–Nelson Prize of theCanadian Mathematical Society. She serves as Trea-surer of the International Council of Industrial and Ap-plied Mathematics and has been a member of several

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editorial boards. Her research interests are in the fieldof nonlinear partial differential equations.

A mathematician and physicist bytraining, François Lalonde holdsa Doctorat d’État (1985) from theUniversité Paris-Sud in the field ofdifferential topology. His fields ofinterest include symplectic topol-ogy, Hamiltonian dynamics, andthe study of infinite-dimensional

groups of transformations. He has been a member ofthe Royal Society of Canada since 1997 and was a Kil-lam Research Fellowship recipient in 2000–2002. Heholds the Canada Research Chair in the field of Sym-plectic Geometry and Topology at the Department ofMathematics and Statistics of the Université de Mont-réal. François Lalonde was a plenary speaker at theFirst Canada–China congress in 1997; part of his workin collaboration with Dusa McDuff was presented inher plenary address at the ICM 1998 in Berlin. He wasalso an invited speaker at the ICM 2006 in Madrid.

Claude Le Bris obtained his doc-torate from the École Polytech-nique in France and his accredi-tation to supervise research fromthe Université Paris Dauphine in1997. His research interests includemathematical analysis and numer-ical methods for partial differen-

tial equations and their applications to molecular sim-ulation, multiscale problems, materials science, andcontinuum mechanics. He is a world-renowned ex-pert in the mathematics of quantum chemistry andthe computation of the electronic structure in quan-tum physics. Claude Le Bris received the Blaise PascalPrize from the Académie des Sciences in 1999, the “CS2002 Prize in Scientific Computing,” and the GiovanniSacchi-Landriani Prize from the Istituto Lombardo in2002. He was Civil Engineer-in-Chief and ResearchScientist at the École Nationale des Ponts et Chausséesand scientific leader of the MICMAC project at INRIA.Claude Le Bris has been a member of several programcommittees of international conferences and thematicyears organized by research centres. He was co-editorof Mathematical Modelling and Numerical Analysis andeditor of the Applied Mathematics Research eXpress. Hehas supervised 12 Ph.D. students and authored fivebooks, 80 articles published in international journals,and 20 articles included into books or conference pro-

ceedings. He has given 90 invited lectures at interna-tional conferences and a series of Aisenstadt lecturesat the CRM (in the fall of 2009).

Claus Michael Ringel receivedthe Diplom (1968) and Ph.D. inMathematics from the Goethe-Universität Frankfurt am Main in1969 and the Habilitation fromthe Eberhard Karls Universität Tü-bingen in 1972. He taught brieflyat Carleton University in Ottawa

(1970–1972). From 1978 to 2010 he was Professor ofMathematics at the Universität Bielefeld in Germany,where he is now Professor Emeritus. He is in additionVisiting Chair Professor at Shanghai Jiao Tong Uni-versity in China. Claus Ringel’s research is in Repre-sentation Theory, the study of concrete realizations ofabstract algebraic structures. His work has been pro-foundly influential in the development of the theory ofrepresentations of finite-dimensional algebras, in par-ticular quivers, hereditary algebras, Ringel–Hall alge-bras, and quantum groups. He has had, and continuesto have, a leading role in a number of SFB (Sonder-forschungsbereich: Collaborative Research Centre) inGermany in the area of representation theory.

Since 2003 Keith F. Taylor hasbeen teaching at Dalhousie Uni-versity where he notably held theposition of dean at the Facultyof Science from 2003 to 2008.He is currently Associate Vice-President Academic for the Out-reach and International Programs.

After obtaining his Ph.D. (1976) at the University ofAlberta, he became Assistant Professor and AssociateProfessor at the University of Saskatchewan. In 1996–1997, Professor Taylor won the Student Union Teach-ing Excellence Award, followed by the Master TeacherAward in 2001. He finds his primary research interestsin Abstract Harmonic Analysis and Wavelet Analysis,Spectral Problems Arising in Chemistry and Technol-ogy Enhanced Pedagogy. He has supervised five Ph.D.theses and nine M.Sc. theses and is still the foundingdirector of the Math Readiness Summer Camps createdin 1996.

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Governance and Scientific Guidance

Akshay Venkatesh has beena professor at Stanford Univer-sity since September 2008. Heobtained his Ph.D. from Prince-ton University in 2002, wasC.L.E. Moore Instructor at MITfrom 2002 to 2004, and a pro-fessor at the Courant Institute

(NYU) from 2004 to 2008. Akshay Venkatesh has re-ceived many prizes and fellowships since the begin-ning of his career, in particular the Sloan Foundation

Fellowship (2007), the Salem Prize (2007), the Davidand Lucile Packard Foundation Fellowship (2007–2012), and the SASTRA Ramanujan Prize (2008). In2010 he was Aisenstadt Chair lecturer at the CRM,within the framework of the thematic semester onNumber Theory as Experimental and Applied Science.His research interests are in number theory and au-tomorphic forms, including representation theory, dy-namics on homogeneous spaces, and arithmetic alge-braic geometry.

GenevièveTanguay, Vice-Rector (Research), Université de Montréal, is an ex-officio member of the InternationalScientific Advisory Committee. Chantal David (Concordia University), Octav Cornea (Université de Montréal),and Odile Marcotte (Université du Québec à Montréal), all Deputy Directors of the CRM, are invited membersof the Committee.

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CRM Administrative and Support Staff

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CRM Administrative and Support Staff

The Director’s Office

François LalondeDirector

Octav CorneaDeputy Director, CRM Prizes

Chantal DavidDeputy Director, Le Bulletin du CRM and joint publi-cations with the AMS and Springer

Odile MarcotteDeputy Director, Annual Report and Coordinationwith Related Fields

Administration

Vincent MasciotraHead of Administration

Julie LabbéSecretary

Guillermo Martinez-ZalceResearch Laboratories Administrative Coordinator

Diane Brulé-De FilippisAdministrative Assistant

Scientific Activities

Louis PelletierCoordinator

Louise LetendreAdministrative Assistant

Sakina BenhimaProject Manager

Computer Services

Daniel OuimetSystems Administrator

André MontpetitOffice Systems Manager (half-time)

Publications

André MontpetitTEX Expert (half-time)

Communications

Suzette ParadisCommunications Officer and Webmaster

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Mandate of the CRM

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Mandate of the CRM

The Centre de recherches mathématiques (CRM) isone of the first and foremost institutes of mathe-

matical research in the world. Indeed it was the first in-ternational institute to introduce the famous thematicprograms (in 1984, at the same time as the MSRI). Theseprograms were created independently by the two in-stitutes and were an inspiration for the tens of insti-tutes that were created in Europe and Asia after 1984.This model turned out to be the most creative andefficient means of fostering research and its applica-tions to state-of-the-art technology. Although the ini-tial programs were concentrated in pure and appliedmathematics, they are now much broader and includeall the fields that use sophisticated mathematical meth-ods: theoretical physics, classical and quantum infor-mation, medical imaging, statistics, probabilistic meth-ods on large-scale networks, etc.

The CRM was created in 1969 by the Université deMontréal through a special grant from the NationalResearch Council Canada. It became an NSERC na-tional research centre in 1984. It is currently fundedby NSERC (Natural Sciences and Engineering ResearchCouncil of Canada), by the Government of Québecthrough the FRQNT (Fonds de recherche du Québec –Nature et technologies), by the Université de Montréal,as well as McGill University, the Université du Qué-bec à Montréal, Concordia University, the Universityof Ottawa, the Université Laval, the Université de Sher-brooke, and by private donations. The mission of theCRM is to support research in mathematics and closelyrelated disciplines and to provide leadership in the de-velopment of the mathematical sciences in Canada.

The CRM carries on its mission and national mandatein several ways:• it organizes each year a series of scientific events on

a specific theme (high-profile lectures, workshops,summer schools, etc.),

• its general program and its multidisciplinary and in-dustrial program provide funding for conferencesand special events at the CRM and across the coun-try,

• each year it invites, through the Aisenstadt Chair,one or more distinguished mathematicians to giveadvanced courses as part of its thematic program,

• it awards four prizes yearly: the CRM–Fields–PIMSPrize recognizing major contributions to mathe-matics, the André-Aisenstadt Prize given for out-standing work carried out by a young Canadianmathematician, the CAP–CRM Prize for excep-

tional achievement in theoretical and mathemati-cal physics, and the CRM–SSC Prize for exceptionalcontributions to statistics in early career,

• it publishes technical reports and books (some of itscollections are published jointly with the AMS orSpringer),

• it has an extensive postdoctoral fellowship program,with more than thirty postdoctoral fellows on site,funded in partnership with other organizations andresearchers,

• it informs the community of its activities through itsnewsletter, Le Bulletin du CRM, and its web site athttp://crm.math.ca/,

• it participates, with the other two Canadian insti-tutes, in groundbreaking national initiatives, for in-stance the Mprime network (formerly Mathemat-ics of Information Technology and Complex Sys-tems). The institutes sponsor the Annual Meetingsof the Mathematical Sciences Societies (CMS, SSC,CAIMS), the development of the mathematical sci-ences in the Atlantic provinces through AARMS,and other activities organized outside the three insti-tutes. They also participate in the National Institutefor Complex Data Structures jointly with the Cana-dian statistical community.

This national mandate is complemented by, and indeedsupported by, a long-standing vocation of promotingresearch in the mathematical sciences in Québec. Forinstance,• the CRM supports research through its ten research

laboratories spanning most of the important areas ofthe mathematical sciences,

• it supports, through partnership agreements, agroup of local researchers chosen mainly from de-partments of mathematics and statistics, but alsocomputer science, physics, economics, engineering,etc.,

• it organizes series of regular seminars and lecturecourses on different areas of the mathematical sci-ences,

• it sponsors joint activities with the Institut dessciences mathématiques (ISM), including the CRM–ISM colloquia, graduate courses offered by distin-guished visitors, and a program of postdoctoral fel-lowships,

• it works actively at developing contacts with indus-try, especially through the Montreal Industrial Prob-lem Solving Workshops.

The CRM fulfils its national mission by involving thelargest possible number of Canadian mathematicians

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in its scientific programs, both as participants and asorganizers. It also supports many events taking placeoutside Montréal and the Province of Québec. TheCRM is reaching out to the general public through twoongoing programs: the Accromαth magazine, whichwas created jointly by the CRM and the ISM and haswon many international prizes and the Prix spécial dela Ministre de l’Éducation (in 2008), and the GrandesConférences du CRM, which allow a broad public toattend lectures given by outstanding international sci-entists.

The director of the CRM is assisted by two managerialstructures: the Board of Directors and the InternationalScientific Advisory Committee. The Advisory Commit-tee is a group of internationally renowned mathemati-cians from Canada and abroad, who approve scientificprograms and thematic years, choose recipients of theAndré-Aisenstadt Prize, and suggest new scientific av-enues to explore.

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