IASThe Institute Letter

Institute for Advanced Study Summer 2011

BY SCOTT TREMAINE

The stability of the solar system is oneof the oldest problems in theoretical

physics, dating back to Isaac Newton.After Newton discovered his famous laws ofmotion and gravity, he used these to deter-mine the motion of a single planet aroundthe Sun and showed that the planet fol-lowed an ellipse with the Sun at one focus.However, the actual solar system contains eight planets, six ofwhich were known toNewton, and eachplanet exerts small,periodically varying,gravitational forceson all the others.The puzzle posed byNewton is whetherthe net effect ofthese periodic forceson the planetaryorbits averages tozero over long times,so that the planetscontinue to followorbits similar to theones they havetoday, or whether

these small mutual interactions graduallydegrade the regular arrangement of theorbits in the solar system, leading even-tual ly to a collision between two planets,the ejection of a planet to interstellarspace, or perhaps the incineration of aplanet by the Sun. The interplanetarygravitational interactions are very small—the force on Earth from Jupiter, the largestplanet, is only about ten parts per millionof the force from the Sun—but the timeavailable for their effects to accumulate is

even longer: overfour billion yearssince the solar sys-tem was formed, andalmost eight billionyears until the deathof the Sun.

Newton’s com-ment on this prob-lem is worth quot ing:“the Planets moveone and the sameway in Orbs concen-trick, some inconsid-erable Irregularitiesexcepted, which mayhave arisen from themutual Actions of

Is the Solar System Stable?

The Institute for AdvancedStudy has received a $100

million unrestricted challengegrant from the Simons Foun-dation and the Charles andLisa Simonyi Fund for Arts andSciences. This donation, whichis the largest since the foun ders’gift establishing the Institute in1930, will serve as the basis fora $200 million campaign tostreng then the Institute’s en-dowment. This grant must bematched by funds from donorswithin the next four years; ad-ditional gifts and pledges of $9 million have already been received. All funds received willbe matched dollar for dollar by the Simons Foundation and the Simonyi Fund.

The $200 million campaign will ensure that the Institute is able to continue its es-sential role in fostering fundamental research in the sciences and humanities. The maingoal of the campaign is to raise new endowment funds that will allow the Institute to keepits draw on the endowment at an acceptable level over the long term. The stability andhealth of the Institute’s endowment is essential for its financial independence because itrelies on endowment income for approximately three-quarters of its operating expenses.This campaign will build upon the successful completion of the Institute’s most recentcampaign, launched in 2004, which raised $135 million from more than 1,500 donors,including Trustees, Faculty, Staff, former Institute scholars, Friends of the Institute, foun-dations and donor-advised funds, and others.

“The Institute is immensely grateful to the Simons Foundation and the Simonyi Fundfor this extremely generous and far-sighted donation, which is of historic importance forthe Institute,” commented Peter Goddard, Director of the Institute. “The Institute was

founded in 1930 by Caroline and Louis Bam-berger, enlightened philanthropists who believedin the need to provide the world’s leading scholarswith the support and facilities that would enablethem to pursue curiosity-driven research thatwould enlarge our understanding of the world,leading to both cultural and practical benefits formankind. Their vision is as relevant today as it waseighty years ago, and this magnificent challengegrant initiates a campaign that will ensure that theInstitute will be able to fulfill its mission in the fu-ture, sustaining a unique scholarly environmentand providing researchers drawn from institutionsaround the world with the freedom they need forfundamental research.”

The Simons Foundation, which seeks to ad-vance the frontiers of research in the basic sciences

IAS Receives $100 Million Challenge Grant:Largest Donation Since Founders’ GiftLead Gifts from the Simons Foundation and the

Charles and Lisa Simonyi Fund for Arts and SciencesLaunch $200 Million Campaign

Einstein Drive, Princeton, New Jersey 08540 www.ias.edu

(Continued on page 3)

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Charles Simonyi

James H. Simons

CLIFF MOORE

CLIFF MOORE

This 240-year-old mechanical model knownas the Rittenhouse Orrery, housed in Pey-ton Hall at Princeton University, shows thearrangement of the solar system.

Black Holes and the Information Paradoxin String Theory

BY JUAN MALDACENA

The ancients thought that space and time were preexisting entities on which motionhappens. Of course, this is also our naive intuition. According to Einstein’s theory

of general relativity, we know that this is not true. Space and time are dynamical objectswhose shape is modified by the bodies that move in it. The ordinary force of gravity isdue to this deformation of spacetime. Spacetime is a physical entity that affects themotion of particles and, in turn, is affected by the motion of the same particles. Forexample, the Earth deforms spacetime in such a way that clocks at different altitudes runat different rates. For the Earth, this is a very small (but measurable) effect. For a verymassive and very compact object the deformation (or warping) of spacetime can havea big effect. For example, on the surface of a neutron star a clock runs slower, at 70 per-cent of the speed of a clock far away.

In fact, you can have an object that is so massive that time comes to a complete stand-still. These are black holes. General relativity predicts that an object that is very massiveand sufficiently compact will collapse into a black hole. A black hole is such a surpris-ing prediction of general relativity that it took many years to be properly recognized as a

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JEAN BOURGAIN, Professor in the School of Mathe-matics since 1994, has been named the IBM von Neu-

mann Professor in the School. He has also been elected tothe National Academy of Sciences as a Foreign Associate.

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ANGELOS CHANIOTIS, Professor in the School of. Historical Studies, has received the 2010 Greek State

Prize for Literature, awarded by the Greek Ministry ofCulture and Tourism. Chaniotis received the prize in theessay category for his book Theatricality and Public Life inthe Hellenistic World, published in Greek (Iraklion, CreteUniversity Press 2009). Chaniotis was also appointed tothe Scientific Board of the Belgian Fonds de la RechercheScientifique (FNRS).

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ERIC S. MASKIN, Albert O. Hirschman Professorin the School of Social Science, has received the

2011 FGC International Award for Economics presentedby the Cristóbal Gabarrón Foundation in Spain.

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AVI WIGDERSON, Herbert H. Maass Professor in. the School of Mathematics, has been elected a

member of the American Academy of Arts and Sciences.Thirteen former Institute Members and Visitors werealso elected to the Academy’s 2011 class.

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ENRICO BOMBIERI, CAROLINE WALKERBYNUM, and ARNOLD J. LEVINE became Profes-

sors Emeritus as of July. Bombieri, a member of the Fac-ulty of the School of Mathematics since 1977, had beenthe IBM von Neumann Professor in the School since1984. Bynum has been a Professor in the School of His-torical Studies since 2003, and Levine has been a Profes-sor in the School of Natural Sciences since 2004.

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CAROLINE WALKER BYNUM, Professor Emerita inthe School of Historical Studies, has been awarded

the Haskins Medal for her book Wonderful Blood: Theol-ogy and Practice in Late Medieval Northern Germany andBeyond (University of Pennsylvania Press, 2007). The medal,

presented by the Medieval Academy of America, is award -ed annually for a book in the field of medieval studies.Bynum recently has published Christian Materiality: AnEssay on Religion in Late Medieval Europe (Zone Books,2011). She is also the recipient of an honorary degreefrom the University of Glasgow.

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Harvard University Press has published volume 3,books 5–8, of The Histories by Polybius (Loeb Classi-

cal Library, 2011), edited by CHRISTIAN HABICHT,Professor Emeritus in the School of Historical Studies,and F. W. Walbank and translated by W. R. Paton.

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ROBERT P. LANGLANDS, Professor Emeritus in the. School of Mathematics, has been awarded an hon-

orary degree by the University of Chicago.

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AVISHAI MARGALIT, former Professor (2006–11). in the School of Historical Studies, received the

2011 Dr. Leopold Lucas Prize at ceremonies in Germanyin May. The prize is presented annually by the Faculty ofProtestant Theology on behalf of the Eberhard Karls Uni-versity, Tübingen. Margalit’s term as George F. KennanProfessor in the School of Historical Studies, which heheld since 2006, ended in July. He is now an HonoraryFellow at the Van Leer Jerusalem Institute.

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RASHID SUNYAEV, the Maureen and John Hendricks. Visiting Professor in the School of Natural Sciences,

has been awarded the 2011 Kyoto Prize in Basic Sciencesby the Inamori Foundation. The award acknowledgesSunyaev’s development of a theory that allows the use offluctuations in cosmic microwave background radiationto explore the expanding universe, and for his contribu-tions to the field of high-energy astronomy.

q

MARIO DRAGHI, an Institute Trustee, has been ap-. pointed President of the European Central Bank

effective November 1. Draghi is currently Governor ofthe Bank of Italy.

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ROGER W. FERGUSON JR., an Institute Trustee, has.been awarded an honorary degree by Michigan State

University. Ferguson is President and Chief ExecutiveOfficer of TIAA-CREF.

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MARTIN REES, an Institute Trustee and formerMember (1969–70, 1973, 1975, 1982, 1992–93,

1996) in the School of Natural Sciences, has been awardedan honorary degree from the University of London. Rees isMaster of Trinity College, University of Cambridge, wherehe is Professor Emeritus of Cosmology and Astrophysics.

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JAMES D. WOLFENSOHN, Trustee Emeritus andChairman Emeritus of the Institute, has been awarded

an honorary degree by the Hebrew University of Jerusalem.Wolfensohn is Chairman of Wolfensohn & Company.

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DAVIDE GAIOTTO, Member (2007–11) in the Schoolof Natural Sciences, has been awarded the 2011 Gri-

bov Medal for uncovering new facets of the dynamics of four-dimensional supersymmetric gauge theories and for his partin finding intricate relations between two-dimensionaltheories of gravity and four-dimensional gauge theories.

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School of Mathematics Member MARK GORESKYand former Member JAYCE GETZ (2007–09) have

been awarded the Ferran Sunyer i Balaguer Prize for theirmonograph “Hilbert Modular Forms with Coefficients inIntersection Homology and Quadratic Base Change,”which will be published in Birkhäuser Verlag’s series

Progress in Mathematics. Getz is Assistant Professor ofMathematics at McGill University.

q

ÁLVARO PELAYO, Member (2010–11) in the School. of Mathematics, has been awarded the Rubio de

Francia Prize by the Royal Spanish Mathematical Society.The prize is awarded annually to a young mathematicianfrom Spain or residing in Spain and is the highest dis-tinction given by the society.

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MICHAEL ASCHBACHER, former Member(1978–79) in the School of Mathematics, has been

awarded the 2011 Rolf Schock Prize in Mathematics bythe Royal Swedish Academy of Sciences. Aschbacher isShaler Arthur Hanisch Professor of Mathematics at theCalifornia Institute of Technology.

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School of Mathematics former Visitor (1983) andMember (1984) DEMETRIOS CHRISTODOULOU

and former Member (1992) RICHARD HAMILTONhavebeen awarded the 2011 Shaw Prize in MathematicalSciences. They were honored for their work on nonlinearpartial differential equations in Lorentzian and Riemann-ian geometry and their applications to general relativityand topology. Christodoulou is a Professor of Mathematicsand Physics at the Eidgenössische Technische HochschuleZürich and Hamilton is the Davies Professor of Mathe-matics at Columbia University.

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INGRID DAUBECHIES, former Member (1999) in theSchool of Mathematics, has been awarded the 2011

Benjamin Franklin Medal in Electrical Engineering by theFranklin Institute for her fundamental discoveries in thefield of compact representations of data, leading to effi-cient image compression. A Professor at Duke University,Daubechies has served on the organizing committee ofWomen and Mathematics, a joint program of the Instituteand Princeton University, since the program’s inception.

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CORMAC Ó GRÁDA, former Member (2007) in theSchool of Historical Studies, has been awarded the Royal

Irish Academy Gold Medal in the Humanities. Ó Gráda isProfessor of Economics at University College Dublin.

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HEISUKE HIRONAKA, former Member (1962–63)in the School of Mathematics, was among four in-

dividuals awarded the 2011 Centennial Medal by Har-vard University’s Graduate School of Arts and Sciences.Hironaka is Professor Emeritus at Harvard.

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CHRISTOPHER P. JONES, former Member (1971–72,1982–83) and Visitor (1987, 1990–91, 2005–06), and

Corinne Bonnet, former Member (2009), both in the Schoolof Historical Studies, have been elected to the Académie desInscriptions et Belles-Lettres in Paris as correspondantsétrangers. Jones is the George Martin Lane Professor of theClassics and of History at Harvard University. Bonnet is aProfessor at the Université de Toulouse II Le Mirail.

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RAMAKRISHNA RAMASWAMY, former Member.(2004–05) in the School of Natural Sciences, has been

named Vice-Chancellor of the University of Hyderabad.q

ERIK VERLINDE, former Member (1988–93) in theSchool of Natural Sciences, has been awarded the

2011 Spinoza Prize by the Netherlands Organization forScientific Research. Verlinde was recognized in part forthe equations he formulated with Edward Witten, CharlesSimonyi Professor in the School of Natural Sciences, andformer Members Herman Verlinde (2008–09) and Rob-bert Dijkgraaf (1991–92, 2002–03). Erik Verlinde is Pro-fessor of Physics at the University of Amsterdam.

C o n t e n t s

2 News of the Institute Community3 Letter from the Director

Institute Board Appoints Two New Trustees5 The Geometry of Random Spaces7 Trade and Geography in the Economic Origins and

Spread of Islam8 Albert O. Hirschman’s Early Institute Years9 Pre-Order Reminder: A Community of Scholars:

Impressions of the Institute for Advanced StudyFrank Gehry: Thinking Out Loud

10 The Institute Lands: Cultivating a True Academic Village

11 Security Versus Civil Liberties and Human Rights12 New AMIAS Board Members Reflect on Institute’s

InfluenceObjectivity: The Limits of Scientific Sight

13 Institute Libraries: A Legacy of DonationsRecord Gifts from Friends of the InstituteContributions to IAS History from Louise Morse

2

Questions and comments regarding the Institute Letter should be directed to

Kelly Devine Thomas, Senior Publications Officer,via email at kdthomas@ias.edu

or by telephone at (609) 734-8091.

Issues of the Institute Letter and other Institute publicationsare available online at www.ias.edu/about/publications.

News of the Institute Community

3

Two new members have been appointed to the Board of Trustees of the Institute forAdvanced Study. Cynthia Carroll, whose appointment was effective May 7, is Chief

Executive of Anglo American plc in London, England. Carmela Vircillo Franklin, Pro-fessor of Classics at Columbia University, was nominated by the Institute’s School of His-torical Studies for a term beginning July 1. Franklin succeeds David A. Hollinger, PrestonHotchkis Professor of American History at the University of California, Berkeley, whoserved a five-year term.

Carroll, who is originally from Princeton, wasappointed Chief Executive of Anglo American inMarch 2007. Anglo American, a major producer ofcopper, nickel, iron ore, coal, phosphates, and nio-bium, is one of the largest diversified mining com-panies in the world, with 85 percent of itsoperations in developing countries. Carroll receiveda B.S. in Geosciences from Skidmore College in1978, an M.S. in Geology from the University ofKansas in 1982, and an M.B.A. from Harvard in1989. She began her career with Amoco in oil andgas exploration in the western United States, instates including Wyoming, Colorado, Utah, andMontana. After earning her business degree, shejoined the Canadian company Alcan and held abroad range of roles, including four years in Ken-tucky as general manager of a packaging company

and three years in Ireland as managing director of Europe’s largest alumina refinery. Herlast five years at Alcan were spent as President and CEO of the Primary Metals business,which operated in twenty-five countries across South America, North America, Europe,and Africa. Carroll serves on the boards of BP and De Beers, and she is Chairman ofAnglo American Platinum Limited, a South African subsidiary of Anglo American. She

is a member of the American Society of Corporate Executives, a former Director of theSara Lee Corporation, and has recently been appointed Chairman of the Stop Organ-ised Abuse Board of the National Society for the Prevention of Cruelty to Children, aBritish nonprofit.

Franklin, a native of Italy, received a B.A. (1971) and Ph.D. (1977) in Classics fromHarvard University. Her work focuses on medieval Latin texts and their manuscripts,and she conducts her research in Europe’s great manuscript repositories, especially theVatican Library and the Bibliothèque Nationale deFrance. In 1977, Franklin joined the faculty of theDepartment of History and the Department ofClassics of St. John’s University in Collegeville,Minnesota, where she served also as Chair of theDepartment of History from 1988 to 1992, andInterim Director of the school’s Hill MonasticManuscript Library. Franklin joined the faculty ofColumbia University in 1993. From 2005 to 2010Franklin served as Director of the American Acad-emy in Rome, an institution for independentresearch in the humanities and advanced work inthe arts. Franklin was awarded the Rome Prize as aMellon Fellow in post-Classical Humanistic Studiesin 1984–85, and was named the Lucy Shoe MerittResident in Classics in 2001–02 by the AmericanAcademy. Additional honors include the Centen-nial Medal of the American Academy in Rome, which she was awarded in 2010, and theHenry Allen Moe Prize in the Humanities from the American Philosophical Society in2003. Franklin is a trustee of the Samuel H. Kress Foundation and a member of the edi-torial board of the journal Traditio. She was elected a Fellow of the Medieval Academyof America in 2008. n

and mathematics across institutions and fields, was founded by James H. Simons, a ViceChairman of the Institute’s Board of Trustees and a Trustee since 2001, and his wifeMarilyn Hawrys Simons. The Charles and Lisa Simonyi Fund for Arts and Sciences,which provides grants to organizations in the arts, sciences, and education, was estab-lished by Charles Simonyi, Chairman of the Institute’sBoard of Trustees and a Trustee since 1997. Both or-ganizations have provided significant support to the In-stitute in the past decade. The Simons Foundation hasfunded numerous initiatives at the Institute, especiallyin the School of Natural Sciences’ Simons Center forSystems Biology, which opened in 2007. The Centerwas named in honor of Jim and Marilyn Simons inrecognition of the Foundation’s generous challengegrant that provided support for operational costs andthe establishment of an endowment fund.

Simons, who serves as Chairman of the Board atRenaissance Technologies LLC and President ofEuclidean Capital LLC and was a Member (1972) inthe Institute’s School of Mathematics, said of the re-cent gift, “The health and viability of the Institute’sendowment will ensure that the Institute can operateat its desired level and maintain the highest stan-dards. Marilyn and I are committed to the Institute’smission and purpose, and are pleased to make thiscontribution.”

Charles Simonyi donated the lead gift toward theInstitute’s previous capital campaign, establishing theKaroly Simonyi Memorial Endowment Fund in mem-ory of his late father. He also endowed the Charles Si-monyi Professorship in Theoretical Physics in 1997,held first and currently by Edward Witten, and has pro-vided support to the Institute’s School of Mathemat-ics. Simonyi Hall, the building that houses the School,was dedicated in 2000 in recognition of his commit-ment to the work of the Institute.

“The Institute’s role in promoting and cultivatingoriginal scholarship in the sciences and humanities is unparalleled,” noted Simonyi,Chairman and Chief Technology Officer of Intentional Software Corporation. “It is of ut-most importance to sustain the work of this institution of international renown and reachwhere scholars have the freedom to pursue their research in an environment dedicatedto the advancement of ideas that change our understanding of the world. Lisa and I arehonored to play a role in building a strong foundation for the Institute’s future.” n

CAPITAL CAMPAIGN (Continued from page 1)

Institute Board Appoints Two New Trustees

Cynthia Carroll Carmela Vircillo Franklin

Letter from the Director

The global financial crisis of recent years has pre-sented great challenges, directly or indirectly, to

all academic institutions. Since its foundation, theInstitute for Advanced Study has depended on its en-dowment to provide the basis of its financial stability:about three-quarters of its core operating expenseshave been provided by income from our endowment.Although our investments have been wisely man-aged, and fared better than those of many other in-stitutions in the financial downturn, it is imperativethat we strengthen our endowment in order to makethe financial future of the Institute secure.

In response to the financial crisis, we succeeded in reducing the Institute’sprojected expenditure by about a fifth for the academic years 2009–12 and, foreach of these three years, the Board of Trustees with magnificent generosity havepersonally provided $10 million per year, reducing the pressure on the endow-ment while its value has been depressed. The economies that have been madehave been chosen carefully so that, as far as possible, they are not damaging theacademic life and work of the Institute, but they cannot all be continued at thislevel indefinitely, and nor should the Institute rely on annual donations of $10million for essential core expenditure.

In order to secure the resources needed in the future for pursuing its missionof fostering fundamental research in the sciences and humanities, providing fi-nancial support and outstanding facilities for its Members and Faculty, the Insti-tute must increase its endowment by $200 million, and so it is launching acampaign to raise this sum. Recently, the Institute received a $100 million chal-lenge grant from the Simons Foundation and the Charles and Lisa Simonyi Fundfor Arts and Sciences (see article, page 1). In order to secure this $100 milliongrant, the Institute has to raise matching donations totaling $100 million withinfour years, and this will achieve our $200 million target.

Last year, we were extremely pleased to receive record levels of donations bothfrom former Members and from the Friends of the Institute. There are many waysof supporting the work of the Institute: with gifts of annual support, major giftsof endowment and program support, or with gifts made in conjunction with es-tate planning. All of these contributions will help the Institute match the $100million challenge grant so generously provided by James H. Simons, Vice Chair-man of the Institute’s Board of Trustees, and Charles Simonyi, Chairman of theBoard. We deeply appreciate all these endorsements of the value of the Institute’smission and the continuing relevance and importance for future generations.

—Peter Goddard

CLIFF MOORE

The Institute wasfounded in 1930 byCaroline and LouisBamberger, enlight-ened philanthropistswho believed in theneed to provide theworld’s leading scholars with thesupport and facilitiesthat would enablethem to pursuecuriosity-drivenresearch that would enlarge ourunderstanding of the world, leading toboth cultural andpractical benefits for mankind.

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prediction. Einstein himself thought it was not a true pre-diction, but a mathematical oversimplification. We nowknow that they are clear predictions of the theory. Fur-thermore, there are some objects in the sky that are prob-ably black holes.

Black holes are big holes in spacetime. They have asurface that is called a “horizon.” It is a surface thatmarks a point of no return. A person who crosses it willnever be able to come back out. However, he will notfeel anything special when he crosses the horizon. Onlya while later will he feel very uncomfortable when he iscrushed into a “singularity,” a region with very highgravitational fields. The horizon is what makes blackholes “black”; nothing can escape from the horizon, noteven light. Fortunately, if you stay outside the horizon,nothing bad happens to you. The singularity remainshidden behind the horizon.

Something surprising happens when we take intoaccount the effects of quantum mechanics. Due to quan-tum mechanical fluctuations near the horizon, blackholes should emit radiation, called Hawking radiation.This is a famous theoretical prediction that StephenHawking made in the seventies. This means that blackholes are not completely black. A black hole can glow,like an ember, or, if it is hot enough, you can even havethe oxymoronic possibility of a white black hole. A blackhole gets hotter the smaller it is. A white black holeshould have the size of a bacterium, and the mass of acontinent. Such black holes, while theoretically possi-ble, are not known to be naturally produced anywhere inthe universe. Black holes that are naturally producedhave masses bigger than the Sun and sizes bigger than afew miles. Such black holes are also supposed to emitHawking radiation, but it is swamped by other matter

falling into the black hole.For this reason, Hawkingradiation has not beendirectly measured. How-ever, the argument lead-ing to it is so solid thatmost scientists who havestudied it think it is a veryclear prediction. The exis-tence of this radiation hasimportant consequences.The first is that blackholes have a temperature.We know that tempera-ture is due to the motionof the elementary con-stituents of the object. Forexample, air is hotter orcolder depending onwhether air molecules aremoving faster or slower. Inthe case of black holes,what is moving? Black

holes only in volve gravity, so what is moving is space-time itself. Since the nineteenth century, we haveunderstood that when we have thermal systems we cancompute a quantity called the “entropy,” which tells usabout the number of microscopic configurations that thesystem has. From Hawking’s formula for the temperatureof a black hole one can also find this entropy. It turns outto be proportional to the area of the horizon, or thesquare of the mass of the black hole. This is also a bitstrange. The entropy of almost every substance grows inproportion to the amount of substance that we have.Here it grows like the square. It is really a case of “themore the merrier.”

A second consequence of Hawking radiation is thatblack holes lose mass, since they are radiating energyaway. Thus, a black hole left alone in an otherwiseempty universe would eventually completely disappear.We call this process “black hole evaporation,” since theblack hole appears to evaporate as a droplet of water.

Hawking radiation from black holes has given rise

to very profound and interesting theoretical puzzles.Einstein has taught us that spacetime is a physicalobject. We also know that all other physical objects,such as those made with matter or radiation, obey thelaws of quantum mechanics. Thus, spacetime should beno different and should also obey the laws of quantummechanics. Any quantum mechanical theory of space-time should be able to describe precisely how black holesform and evaporate. It should also give a precise expla-nation for the entropy of a black hole.

Here one finds an interesting paradox. Classically,all the information making the black hole has falleninside. On the other hand, Hawking radiation impliesthat the black hole emits thermal radiation. This ther-mal radiation apparently carries no information about

the things that fell in, since this radiation is generatedin the vicinity of the horizon. Thus the black hole canform in many different ways but it appears to evaporatealways in the same way. This is a contradiction withstandard quantum mechanics. In quantum mechanics(as in classical mechanics) the information about a sys-tem is not lost. Different initial conditions lead to dif-ferent outcomes. It can be the case that sometimes theoutcomes are very similar. For example, if one puts thisarticle in a shredder, one seems to lose what was written

on it. However, one could, in principle, put it backtogether. Hawking suggested that black holes imply thatthis basic principle of quantum mechanics would nothold in the presence of gravity. Namely, the radiationcoming out of black holes would be completely thermaland devoid of the information of what fell into blackholes. Thus, black holes appear to be sinks of informa-tion, perverse monsters that threaten the fundamentallaws of quantum mechanics.

String theory is a theory being constructed todescribe the quantum mechanics of spacetime. Assuch, the theory should explain whether black holesare consistent with quantum mechanics or not. In fact,since string theory obeys the usual principles of quan-tum mechanics, we expect that information should not

be lost in black holes. For this reason the problem ofinformation loss was actively studied during thenineties. The problem was difficult in the original for-mulation of string theory because the quantum space-time was described by starting with a flat spacetime andthen considering small quantum fluctuations, or ripples,that propagate in it. As long as these ripples interactweakly with each other, the theory is relatively simple.However, in order to form a black hole you need astrong deviation from a flat spacetime. You need to puta lot of these ripples together, and by the time the blackhole forms, the simplest formulation of string theorybecomes unmanageable.

In the mid-nineties, Joseph Polchinski (at the Uni-versity of California, Santa Barbara) made a break-through by discovering that string theory containsother objects, called D-branes. They have a strangename for reasons that are not important for us. You canmentally give them any other name that you find morepleasant. These are particle-like objects that are heav-ier than the spacetime ripples we discussed above.Nevertheless, one can give a very precise descriptionfor them within the rules of string theory. It soonbecame clear that they were ideally suited for studyingblack holes.

The description of a single D-brane is fairly simple. Asingle D-brane is very similar to a particle; it is charac-terized by its position in space. However, a single D-brane is not heavy enough to curve spacetime in asignificant way. So, we need to bring many D-branestogether. When we bring them together, there is a sur-prising new symmetry that emerges. In ordinary quan-tum mechanics, elementary particles are identical, inthe sense that there is no way to distinguish them. Thefull description is completely invariant under the inter-change of any two identical elementary particles, such astwo electrons. D-branes are invariant under a biggersymmetry group: a full continuous symmetry, called agauge symmetry. (For the mathematically oriented:this is the group SU(N) versus the permutation groupSN). When N D-branes come together, the positionsof the branes become N x N matrices. A matrix is anarray of numbers. We would have expected that Nbranes are described by N positions, the positions ofeach of the objects individually. However, we find thatthey are described by N2 numbers. The dynamics ofthese N2 variables is governed by a gauge theory. Gaugetheories are very important for the description of nature;we use them to describe three of the forces (the electro-magnetic, the weak, and the strong). Now, if we want toseparate the D-branes by a big amount, we find thatthere is a force that does not allow them to be separatedunless the matrices are diagonal, reducing then to theusual description in terms of N identical particles. Whenall these D-branes are close together, the number of pos-sible ways to arrange them grows very fast with its num-ber. It grows like N2, rather than the N expected for ausual extensive system.

This has become a bit abstract, so let us make ananalogy. Say D-branes are people. Imagine that we havea group of N people (say N is a big number, e.g., a thou-sand). Now imagine that each person can be happy orsad. The entropy is just the information that you needto completely specify the emotional state of everybody.In this case you need to specify N bits of information:whether each of the N persons is happy or sad. If N is athousand, you need a kilobit of information. On theother hand, imagine that each person can like or dislikeevery other person. Now to capture the complete set oflikes or dislikes of everybody you need to give N2 bits ofinformation. If N is a thousand, you need a megabitof information. The case of black holes is similar tothis latter situation, where one has to keep track of vari-ables that involve pairs of D-branes, rather than singleD-branes. In this analogy, you can only separate the D-branes when they dislike (and are disliked by) all the

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BLACK HOLES (Continued from page 1)

Juan Maldacena, whofirst came to the Insti-tute as a Member in1999, has been a Pro-fessor in the School ofNatural Sciences since2002. He continuesto study a relation-ship he has proposedbetween quantumgrav ity and quantumfield theories in aneffort to further under-stand the deep connec-tion between blackholes and quantumfield theories as wellas connections be -tween string theoryand cosmology. Spacetime should also obey the laws of

quantum mechanics. Any quantummechanical theory of spacetime shouldbe able to describe precisely how black

holes form and evaporate.

A black hole in a negatively curved spacetime is described in termsof a quantum mechanical system living on the boundary of thespacetime. The boundary is the outer rim of the figure above(adapted from a picture of hyperbolic space by M. C. Escher).

(Continued on page 7)

BY MATTHEW KAHLE

Isometimes like to think about what it might be like in-side a black hole. What does that even mean? Is it re-

ally “like” anything inside a black hole? Nature keeps usfrom ever knowing. (Well, what we know for sure is thatnature keeps us from knowing and coming back to tellanyone about it.) But mathematics and physics makesome predictions.

John Wheeler suggested in the 1960sthat inside a black hole the fabric of space-time might be reduced to a kind of quantumfoam. Kip Thorne described the idea in hisbook Black Holes & Time Warps as follows(see Figure 1).

“This random, probabilistic froth is thething of which the singularity is made, andthe froth is governed by the laws of quan-tum gravity. In the froth, space does nothave any definite shape (that is, any def-inite curvature, or even any definitetopology). Instead, space has variousprobabilities for this, that, or another cur-vature and topology. For example, insidethe singularity there might be a 0.1 percentprobability for the curvature and topologyof space to have the form shown in (a),and a 0.4 percent probability for the formin (b), and a 0.02 percent probability forthe form in (c), and so on.”

In other words, perhaps we cannot sayexactly what the properties of spacetimeare in the immediate vicinity of a singular-ity, but perhaps we could characterize theirdistribution. By way of analogy, if we knowthat we are going to flip a fair coin a thou-sand times, we have no idea whether any particular flipwill turn up heads or tails. But we can say that on aver-age, we should expect about five hundred heads. More-over, if we did the experiment many times we shouldexpect a bell-curve shape (i.e., a normal distribution),so it is very unlikely, for example, that we would seemore than six hundred heads.

To get a feel for a random space, here is an examplethat you can make at home. All you need is a deck ofplaying cards, some paper, scissors, and tape.

Make a mini-deck of twelve playing cards: ace, two,three, four, five, six, seven, eight, nine, ten, jack, queen.Cut four paper triangles. Label their sides A–Q (to corre-spond to your deck of cards) as in Figure 2. Shuffle thecards, then take the top two cards from the deck. Say thecards are five and seven: tape the side labeled five to theside labeled seven, keeping the printed side of each trian-gle side up. (This ensures that you end up with an ori-entable surface.) Again, take the top two cards from thedeck, tape the corresponding triangle sides, and repeatuntil you have used all twelve cards and alltwelve sides are taped. As you get toward theend, you might have to really bend up yourpaper. But after gluing six pairs, you aremathematically certain to have a surface.What is uncertain is which surface.

One might end up with a surface home-omorphic (i.e., continuously deformable)to a sphere or a torus. But one might alsoend up with two spheres or a sphere and atorus, so the surface need not be connected.However, if one did this with many trian-gles, it would be very likely that the surface would beconnected and the main question would be its genus––i.e., how many “handles” or “holes” does it have. Itturns out that if one glues together n triangles random-ly in this way, one should expect a surface of genusroughly n/4, on average. (This is a theorem of NicholasPippenger and Kristin Schleich, and independently ofNathan Dunfield and William Thurston.)

It turns out that this relatively simple model of arandom space already encodes a lot of physics as ntends to infinity, and in fact one of the motivations tostudy it is that it serves as a two-dimensional discreteanalogue of quantum gravity. So random spaces pro-vide a mathematical model of something of funda-mental interest in theoretical physics and cosmology.

Random spaces also provide interesting models

within mathematics itself, as well as useful construc-tions in theoretical computer science. To mathemati-cians and theoretical computer scientists, one of theimportant discoveries of the last fifty years is that ran-dom objects often have desirable, hard to come by

otherwise, properties. There are many examples of thisparadigm by now, but one of the first was in Ramseytheory.

A combinatorial fact: among any party of six people,there must be either three mutual acquaintances orthree mutual nonacquaintances. This isn’t necessarilytrue for five people. Let R(n) denote the smallest num-ber of people that guarantees that if you have a party of

R(n) people there are either n mutual acquaintances orn mutual non-acquaintances. So, taking the exampleabove, R(3)=6. It is also known that R(4)=18, i.e.,among any eighteen people, there must be either fourmutual acquaintances or four mutual non-acquain-tances. But R(n) isn’t known for any larger n.

Paul Erdo''s suggested that if advanced aliens threatenthe Earth, telling us they will blow us up unless we tell

them R(5) within a year, we should puttogether all the best minds and use all ourcomputer resources and see if we can figure itout. But if they ask for R(6), he warned, weshould probably attack first.

When mathematicians can’t computesomething exactly, we often look for boundsor estimates. In the case of Ramsey theory,lower bounds come from somehow arrang-ing a party with not too many mutualacquaintances or nonacquaintances. As thenumber of people gets large, to describe thiskind of structure explicitly gets unwieldy,and after decades of people thinking aboutit, no one really knows how to do it verywell. The best lower bounds we know comefrom the simple strategy of assigningacquaintanceship randomly.

This is a surprising idea at first, but itturns out to be powerful in a variety of set-tings. In many problems one wants tomaximize some quantity under certainconstraints. If the constraints seem to forceextremal examples to be spread aroundevenly, then choosing a random exampleoften gives a good answer. This idea is theheart of the probabilistic method.

Ramseytheory is one

of many examples wherethe probabilistic methodhas been applied to com-binatorics. This methodhas also been applied inmany other areas ofmathematics, includingmetric geometry. Forexample, Jean Bourgain(Professor in the Schoolof Mathematics) showedthat every finite metricspace could be embeddedin Euclidean space withrelatively low distor-tion—his method was tocarefully choose a random embedding and show that ithas low distortion with high probability.

The probabilistic method has many applications intheoretical computer science as well. For example, a net-

work made by randomly joining pairs ofcomputers will be fairly robust, in the sensethat everything might still be connectedeven if a few cables fail. Such networks arecalled expanders, and expanders are a veryactive area of research. Although randommethods construct expanders easily, untilrecently the only explicit examples camefrom deep number-theoretic considerations.Peter Sarnak and Avi Wigderson (Professorsin the School) have made fundamental con-tributions to the theory of expanders.

There has been recent interest in finding higher-dimensional analogues of expanders, and it has now beenshown that certain random spaces, similar to thosedescribed above, have expander-like properties. It seemslikely that these new higher-dimensional expanders willfind applications in spectral clustering and topologicaldata analysis, in sparsification of cell complexes, andprobably in as yet unforeseen ways as well. n

5

The Geometry of Random Spaces

Matthew Kahle, aMember (2010–11)in the School of Math-ematics, is interestedin various interactionsof probability and sta-tistical mechanics withtopology, geometry,and combinatorics.Beginning in the fall,he will be an AssistantProfessor at the OhioState University.

John Wheeler suggested in the 1960s that inside a black hole the

fabric of spacetime might be reduced to a kind of quantum foam....

Perhaps we cannot say exactly whatthe properties of spacetime are in theimmediate vicinity of a singularity, but perhaps we could characterize

their distribution.

Figure 1. From Black Holes and Time Warps: Einstein’s Outrageous Legacy,by Kip S. Thorne (W. W. Norton & Company, Inc., 1994)

Figure 2

USED W

ITH PERMISSIO

N O

F THE PUBLISHER

Comets and Planets upon one another, and which willbe apt to increase, till this System wants a Reforma-tion.” Evidently Newton believed that the solar systemwas unstable, and that occasional divine interventionwas required to restore the well-spaced, nearly circularplanetary orbits that we observe today. According tothe historian Michael Hoskin, in Newton’s world view“God demonstrated his continuing concern for hisclockwork universe by entering intowhat we might describe as a perma-nent servicing contract” for the solarsystem.

Other mathematicians have alsobeen seduced into philosophical spec-ulation by the problem of the stabilityof the solar system. Quoting Hoskinsagain, Newton’s contemporary andrival Gottfried Leibniz “sneer[ed] atNewton’s conception, as being that ofa God so incompetent as to bereduced to miracles in order to rescuehis machinery from collapse.” A cen-tury later, the mathematician PierreSimon Laplace was inspired by thesuccess of celestial mechanics tomake the famous comment that nowencapsulates the concept of causalor Laplacian determinism: “An intel-ligence knowing all the forces actingin nature at a given instant, as well asthe momentary positions of all thingsin the universe, would be able to com-prehend in one single formula themotions of the largest bodies as well asthe lightest atoms in the world, pro-vided that its intellect were sufficient-ly powerful to subject all data toanalysis; to it nothing would be uncer-tain, the future as well as the past would be present toits eyes. The perfection that the human mind has beenable to give to astronomy affords but a feeble outline ofsuch an intelligence.”

Many illustrious mathematicians and physicists haveworked on this problem in the three centuries sinceNewton, including Vladimir Arnold, Boris Delaunay,Carl Friedrich Gauss, Andrei Kolmogorov, JosephLagrange, Laplace, Jürgen Moser, Henri Poincaré,Siméon Poisson, and others. Several “proofs” of stabili-ty have been announced in the course of these labors;these have all been based on approximations that arenot completely accurate for our own solar system andthus do not prove its stability. Nevertheless, research onthis problem has led to many new mathematical toolsand insights (perturbation theory, the KAM theorem,etc.) and inspired the modern disciplines of nonlineardynamics and chaos theory.

The long-term behavior of the solar system is alsorelevant to a variety of other issues. Particle accelera-

tors such as the Large Hadron Collider must guide pro-tons for over a hundred million orbits, a problemsimilar in several respects to maintaining the planetson stable orbits for the lifetime of the solar system. Thedelivery of meteorites to Earth from their birthplace inthe asteroid belt is driven by the long-term evolutionof asteroid orbits due to forces from Jupiter and otherplanets. The primary mechanism that drives climatechange and ice ages on timescales of tens of thousands

of years is the periodic variation in the Earth’s orbit dueto forces from the other planets. The discovery of hun-dreds of extrasolar planetary systems in the last twodecades raises the tantalizing possibility that some orall of their properties are determined by the require-ment that these systems have been stable for billions ofyears. In a different arena, some astronomers argue thatRobert Frost’s famous poem “Fire and Ice” was inspired

by the possible fates of the Earth at the demise of thesolar system.

The most straightforward way to solve the problemof the stability of the solar system is to follow the plan-etary orbits for a few billion years on a computer. Allof the planetary masses and their present orbits areknown very accurately and the forces from other bod-ies—passing stars, the Galactic tidal field, comets,asteroids, planetary satellites, etc.—are either easy toincorporate or extremely small. There are two mainchallenges. The first is to devise numerical methodsthat can follow the motions of the planets with suffi-cient accuracy over a few billion orbits; this was solvedby the development in the 1990s of symplectic inte-gration algorithms, which preserve the geometricalstructure of dynamical flows in multidimensionalphase space and thereby provide much better long-term performance than general-purpose integrators.The second challenge was the overall processing timeneeded to follow planetary orbits for billions of years;this was solved by the exponential growth in speed ofcomputing hardware that has persisted for the last fivedecades. At the present time, following planetary sys-tems over billion-year intervals is difficult mostlybecause it is a serial problem––you have to follow theorbits from 2011 to 2020 before you can follow themfrom 2021 to 2030––whereas most of the computa-tional speed gains of the last few years have beenachieved by parallelization, the distributing of a com-puting problem among hundreds or thousands ofprocessors that work simultaneously.

So what are the results? Most of the calculationsagree that eight billion years from now, just before theSun swallows the inner planets and incinerates theouter ones, all of the planets will still be in orbits verysimilar to their present ones. In this limited sense, thesolar system is stable. However, a closer look at theorbit histories reveals that the story is more nuanced.After a few tens of millions of years, calculations using

slightly different parameters (e.g., different planetarymasses or initial positions within the small rangesallowed by current observations) or different numeri-cal algorithms begin to diverge at an alarming rate.More precisely, the growth of small differenceschanges from linear to exponential: at early times, thedifferences in position at successive time intervalsgrow as 1 mm, 2 mm, 3 mm, etc., while at later times

they grow as 1 mm, 2 mm, 4 mm, 8mm, 16 mm, etc. This behavior is thesignature of mathematical chaos, andimplies that for practical purposesthe positions of the planets areunpredictable further than about ahundred million years in the futurebecause of their extreme sensitivityto initial conditions. As an example,shifting your pencil from one side ofyour desk to the other today couldchange the gravitational forces onJupiter enough to shift its positionfrom one side of the Sun to the othera billion years from now. The unpre-dictability of the solar system oververy long times is of course ironicsince this was the proto typical systemthat inspired Laplacian determinism.

Fortunately, most of this unpre-dictability is in the orbital phases ofthe planets, not the shapes and sizes oftheir orbits, so the chaotic nature ofthe solar system does not normallylead to collisions between planets.However, the presence of chaosimplies that we can only study thelong-term fate of the solar system in astatistical sense, by launching in ourcomputers an armada of solar systems

with slightly different parameters at the present time––typically, each planet is shifted by a random amount ofabout a millimeter––and following their evolution.When this is done, it turns out that in about 1 percentof these systems, Mercury’s orbit becomes sufficientlyeccentric so that it collides with Venus before the death

of the Sun. Thus, the answer to the question of the sta-bility of the solar system––more precisely, will all theplanets survive until the death of the Sun––is neither“yes” nor “no” but “yes, with 99 percent probability.”

There remain two intriguing facts that lead to aplausible speculation. First, the future time required forthe loss of Mercury is rather similar, within a factor offive or so, to the past time at which the solar systemwas born. Second, the solar system is nearly “full,” inthe sense that there are few places where we couldinsert an additional planet without causing immediateinstability. Both of these facts are explained naturallyif the solar system began with more planets, in a con-figuration that was unstable on timescales much small-er than its current age. As time passed, the system lostmore and more planets and thereby gradually self-organized into a more and more stable state. In thisprocess, the time required to lose the next planetwould quite naturally be a few times the current age.There would be few fossil traces of these lost siblingsof the Earth. n

6

SOLAR SYSTEM (Continued from page 1)

Scott Tremaine first came to the Institute for Advanced Study as a Member in 1978 and has beenthe Richard Black Professor in the School of Natural Sciences since 2007. He has made seminalcontributions to understanding the formation and evolution of planetary systems, comets, blackholes, star clusters, galaxies, and galaxy systems.

Shifting your pencil from one side ofyour desk to the other today couldchange the gravitational forces onJupiter enough to shift its position

from one side of the Sun to the other a billion years from now.

ANDREA K

ANE

Some astronomers argue that Robert Frost’s famous poem “Fire

and Ice” was inspired by the possiblefates of the Earth at the demise of

the solar system.

other D-branes, so the number of configurations becomesmuch smaller.

A large number of D-branes is heavy enough to warpthe spacetime around them and to produce a black hole.In order to produce a black hole with some temperatureit is necessary to excite these N2 degrees of freedom. Thisleads to a precise microscopic accounting for the entropyof the black holes, as shown by Andrew Strominger andCumrun Vafa (both former Members of IAS). These N2

degrees of freedom produce a highly entangled state thatcannot be described in terms of the motion of the indi-vidual particles. However, it can be described very pre-cisely in terms of the gauge theory of the N x Nmatrices.This gauge theory is not particularly different from theones we use to describe the strong force in nature. Somedetails are different. However, in some very importantrespects it is the same. First, it obeys the usual rules ofquantum mechanics. Second, it lives on a fixed space-time—in this case, the point in spacetime where thebranes are sitting.

Actually, this leads us into an apparent contradic-tion. On the one hand, we said that we can describe thebranes in terms of a gauge theory living at a spatialpoint. On the other hand, we said that the branes forma black hole, which has a non-zero horizon size.

In fact, in string theory, these two descriptions areviewed as equivalent. The gauge theory is describing thewhole region around the black hole. If we view the black

hole from very far away, it looks like a point—that is whythe matrices live at a point. On the other hand, the matri-ces also give rise to the whole spacetime region aroundthe horizon of the black hole. This is the gauge/gravitycorrespondence proposed by myself and Edward Witten(at IAS) and Steven Gubser, Igor Klebanov, and Alex -ander Polyakov (at Princeton University).

The gauge theory gives a precise description of theblack hole and its surrounding geometry. It is describedin terms of a perfectly ordinary quantum mechanicalsystem. This explains its entropy. It also gives a com-pletely quantum mechanical description of the blackhole and the spacetime around the black hole. This

description is sometimescalled “holographic” becausethe whole spacetime emer gesdynamically from a quantummechan ical description thatlives in a smaller number ofdimensions. (An ordinaryhologram is a two-dimen-sional surface that producesa three-dimensional imagewhen it is illuminated.)

Going back to the analogy of the group of people andthe pattern of likes and dislikes, the idea is that thewhole spacetime is encoded in the pattern of likes anddislikes among the various people. A spacetime ripple isa change in that pattern. The “gauge theory” is a simpledynamical law that says how this pattern changes.

This description has been explored actively here at theInstitute and elsewhere. It is best understood in very spe-cial configurations in string theory. However, similardescriptions are expected to be valid for black holes ingeneral. These theoretical developments were made withthe goal of showing that black holes behave like ordinaryquantum mechanical objects. More recently, the samerelation is being explored in order to model strongly inter-acting quantum systems via black holes. Thus, in somesense, black holes have become a source of information,rather than the sinks they were feared to be! n

BY STELIOS MICHALOPOULOS

Karl Marx linked the structure of production to theformation of institutions. According to Marx, reli-

gion is like any other social institution in that it is de-pendent upon the economic realities of a given society,i.e., it is an outcome of its productive forces. In contrast,Max Weber highlighted the independent effect of reli-gious affiliation on economic behavior. Weaving theseinsights together, my research with Alireza Naghavi andGiovanni Prarolo of the University of Bologna proposesthat geography and trade opportunities forged the Is-lamic economic doctrine, which in turn influenced theeconomic performance of the Muslim world in thepreindustrial era. Since Islam emerged in the Arabianpeninsula when land dictated productive decisions, thearrangement of Islamic institutions had to be compati-ble with the conflicting interests of groups residingalong regions characterized by a highly unequal distri-bution of agricultural potential.

In particular, we argue that the unequal distributionof land endowments conferred differential gains fromtrade across regions. In such an environment, it wasmutually beneficial to establish an economic systemthat dictated both static and dynamic income redistri-bution. The latter was implemented by enforcing anequitable inheritance system, increasing the costs ofphysical capital accumulation, and rendering invest-ments in public goods, through religious endowments,increasingly attractive. These Islamic economic princi-ples allowed Muslim lands to flourish in the preindus-trial world but limited the potential for growth inthe eve of large-scale shipping trade and industrializa-tion. In a stage of development when land attributesdetermine productive capabilities, regional agricultur-al suitability plays a fundamental role in shaping thepotential of a region to produce a surplus and thusengage in and profit from trade. Based on this idea, wecombined detailed data on the distribution of region-al land quality and proximity to pre-Islamic traderoutes with information on Muslim adherence acrosslocal populations.

To mitigate concerns related to the endogeneity ofcontemporary political boundaries, we arbitrarily divid-ed the world into geographic entities, called virtualcountries, and found that Muslim populations dominat-ed more unequally endowed places closer to preindus-trial trade routes. Naturally, modern states have affectedreligious affiliations via state-sponsored religion. Never-theless, the above pattern remains robust when weaccount for these state-specific histories.

As part of our study, we assembled information onthe traditional location of ethnic groups. Consistentwith the hypothesis that Islamic economic principlesprovided an attractive social contract for populationsresiding along productively unequal regions, we foundthat Muslim adherence increased with the degree ofgeographic inequality. Islam spread successfully amonggroups historically located in agriculturally poor regionsfeaturing few pockets of fertile land and in countriescharacterized by unequal land endowments. It was in

these areas that the Islamic institutional arrangementproved appealing to the indigenous populations.

Islam spread both via conquests and via the peace-ful adoption of the doctrine. Because our theory focus-es on the economic conditions conducive to thevoluntary adoption of Islam, we concentrated onregions outside the Muslim empires. Doing so allowedus to single out the role of geography and trade andmitigate concerns related to the process of conversionwithin Muslim empires arising from coercion, Arabmigration, and differential taxation.

The acceptance of Islam in most of Inner Asia,Southeast Asia, and sub-Saharan Africa is well knownto have occurred through contacts with merchants.The independent role of proximity to pre-Islamic traderoutes, as a means of gaining access to the Muslim trad-ing network, was also an important contributor. Thelocation of Indonesia along highly lucrative commer-cial routes, for example, precipitated the spread ofIslam since the eleventh century despite a fairly equal-ly distributed regional agricultural potential.

We do not suggest that Muslim economic principlesare unique to the Islamic religion. Similar principles ofwealth redistribution may be found in other Abraham-ic religions at certain points in history, but in thecourse of time they became less focal. We propose thatthese principles emerged and persisted in Islam becauseof a geography characterized by highly unequal agricul-tural endowments, which shaped the economic aspectsof the Islamic religious doctrine. The fact that Muslimmerchants dominated African and Eurasian traderoutes between the seventh and fifteenth centuriesimplies that the indigenous populations in Asia andAfrica were primarily exposed to the Muslim doctrine.Even if one were to take the view that Christianity andIslam are doctrinally close substitutes, historically theeffective choice that tribal areas outside Muslimempires faced was either to become Muslim or to retaintheir tribal religions. Along these lines we find thatlocal, tribal religions persisted in territories with rela-tively equal endowments, whereas Muslim adherenceincreased systematically in territories close to traderoutes featuring unequal land endowments. n

7

Trade and Geography in the Economic Origins and Spread of Islam

Recommendedreading: TheBlack Hole Warby LeonardSusskind (Little,Brown and Company, 2008)

Stelios Michalopoulos, the Deutsche Bank Member (2010–11)in the School of Social Science, is Assistant Professor of Eco-nomics at Tufts University.

CLIFF MOORE

These theoretical developments were made with the goal of showingthat black holes behave like ordinary

quantum mechanical objects. More recently, the same relation isbeing explored in order to model

strongly interacting quantum systemsvia black holes.

BLACK HOLES (Continued from page 4)

BY JEREMY ADELMAN

Albert O. Hirschman became a permanent Facultymember of the Institute in 1974, moving from Har-

vard’s economics department to join Clifford Geertz inthe creation of the School of Social Science. By then,Hirschman was not just famous for his writings abouteconomic development and his analyses of Latin Amer-ican political economies. His Exit, Voice, and Loyalty:Responses to Decline in Firms, Organizations, and States(Harvard University Press, 1970) had made him one ofthe country’s renowned social scientists.

Behind the scenes, however, his concernswere shifting; he was, he said, “retreating” intohistory and the study of the intellectual founda-tions of political economy. Retreat did not severhis interest in the present. If anything, it was thepresent that gnawed at him, especially in LatinAmerica. In late summer 1973, Hirschmanbecame the Chair of the Social ScienceResearch Council Joint Committee for LatinAmerican Studies. Ten days later, he learned ofthe violent overthrow of Chile’s socialist Presi-dent, Salvador Allende, whom Hirschman hadmet and admired as an example of a “reform-monger,” a type he celebrated in Journeys TowardProgress (Twentieth Century Fund, 1963), hisepic of Latin America’s hopeful 1960s. Allende’sdeath and the disappearance of friends and for-mer students, indeed the wave of authoritarianregimes sweeping the region, shattered the opti-mism that had buoyed his thinking.

If, by 1976, Hirschman’s bias for hope wasfraying, it was hard for the outer world to see.As Hirschman was planning a trip to LatinAmerica, McGeorge Bundy, President of theFord Foundation, asked Hirschman and Geertzto sit down and converse about the theme “the hungry,crowded, competitive world.” The idea was to raisesome critical perspectives that would guide the founda-tion’s thinking about their funding priorities for thefuture. The very topic of the gathering conveyed theprevailing mood. Hirschman was determined to chal-lenge it by, as he told Bundy, showing “that I am less ofa mindless optimist than people (and sometimes myclosest colleagues and friends) tend to think.” The con-versation began with its dark tone; Hirschman immedi-ately resisted it with a reminder to put social scientificanalysis into a broader historic context. The naive1950s believed “all good things go together”: increaseGDP and get democracy; free people, and they willinvest. “It was a simplistic model,” he recalled. “Butnow we have come in a sense to the inverse idea, thatall bad things go together”: growth is bunk; humanrights exist to be trampled on. But this “dismal diagno-sis,” according to Hirschman, was “probably just aswrong as the earlier one, and I’m also a little bit suspi-cious of where it leads us.” Geertz, who knewHirschman as well as anyone, and was one of the friendswho poked fun at his resilient hopefulness, chimed in:“Albert always wants to look on the bright side.” Geertzwas not the first to point out that for Hirschman “truthlies not at the extremes but in the middle.”

Hirschman believed that the divide between hopeand hopelessness, optimism and pessimism, was a falseone. It was not a matter of whether the overall story wasbleak or uplifting, but how it was told, for the epic pas-sage of social change was riddled with chance andchoice. He wanted to get at social scientists’ mindsets,why they persisted “in thinking of having only one thinghappen, and everything else will coalesce around it, andwe’ll come out all right.” Why, asked Hirschman, do “weonly have one ‘new key’ at a time?”

His solution was not, however, to exhort or to“voice,” but rather a kind of “exit,” a “withdrawal tohistory”—“to dwell for a while among the politicalphilosophers and political economists of the seven-

teenth and eighteenth centuries” in search of early pat-terns of thinking about capitalism and democracy.

A phrase from Montesquieu’s Spirit of the Laws wasfiled away in his archive of favorite quotes: “It is fortu-nate for men to be in a situation where, though theirpassions may prompt them to be wicked, they have nev-ertheless an interest in not being so.” The phrase would,fittingly, be the epigraph for the manuscript The Passionsand the Interests: Political Arguments for Capitalism Beforeits Triumph (Princeton University Press, 1977). In it wasnestled the foundational paradox that motivatedHirschman. Marxists and romantics alike criticized cap-

italism for its lack of moral compass, for having nar-rowed individual drives to base motives, and theydenounced the system for realizing precisely what it wasoriginally hoped would happen, presenting a choice tomen between the “wicked” and an “interest in not beingso.” Hirschman discovered that a war was being wagedover the very concept of human nature; for several cen-

turies, Hirschman noted, “man was widely viewed as thestage on which fierce and unpredictable battles werefought between reason and passion or, later, among thevarious passions.”

Moving to the Institute brought Hirschman face toface with new currents in intellectual history. The histo-ry of ideas was, in some respects, a polar extreme todevelopment studies and its concerns with roads, infla-tion, and agrarian reform. For Hirschman, however, itwas not such a stretch to see the links between theseuniverses; as we know from his conversations with LatinAmerican colleagues, he was always alert to the ways inwhich ideologies and intellectuals shaped the thinkingof policymakers who fashioned the spectrum of peoples’choices. Now it was Machiavelli, Montesquieu, andAdam Smith who were conversing with him about thesame themes. Mediating his retreat into early ideologicalformulae was a shift in intellectual history from the studyof the inherent significance of classic thought to the

meaning of a treatise derived from a reconstruction ofthe political idiom of when and where it was written. Akey figure was Quentin Skinner, who himself had movedfrom England to take up a sojourn at the Institute, firstin the School of Historical Studies, and then in SocialScience until his return to Cambridge.

Notes of conversations and readings shared with Skin-ner and others were scribbled on Hirschman’s ubiquitousyellow pads. When the first draft of The Passions and theInterests was complete, he shared it with friends at theInstitute. To Skinner, Hirschman’s arrival at Adam Smithand economics was less a concern than a departure with

Machiavelli and politics, the beginnings of anintellectual arc to which the manuscript wasdevoted. Skinner spent more time teasing apartnuances that Hirschman—in his brevity—glossed over (for instance, the difference betweenhonor and glory in The Prince, which Hirschmanlumped together, but which Skinner felt repre-sented quite different ideals in the Renaissance;perhaps Calvin would be a better example thanHobbes as an illustration of someone who imag-ined the state as a repressor of man’s passions?).Skinner also directed Hirschman to an alterna-tive fount for thinking about the ideal of activecitizenship and commerce in Machiavelli, not ofThe Prince, which is where Hirschman had start-ed out, but in the Discorsi, where Hirschman wentafter Skinner pointed it out.

In the examination of discourses about marketlife and behavior by seventeenth- and eigh-teenth-century political economists, Hirschmanfocused on passions-oriented anxiety and the useof language to control and channel socially usefulpursuits. At the core of The Passions and theInterests was an observation about how verbalmessages became absorbed or “imposed them-

selves”––how words themselves had agency. To be effec-tive, interest-propelled activity by governments andindividuals required a light hand, invisible or not. This isa reason why, as Skinner pointed out to Hirschman, theverb “to meddle” acquired a derogatory currency over thecourse of the eighteenth century.

The Passions and the Interests was itself an argumentfor a historic middle ground between nostalgia for lostpassions and a celebration of “the love of lucre.”Hirschman did not want to celebrate a model of acquis-itive citizens; nor did he think restoring the passions wasan especially good idea either. He was a modernist. Hiswas a vision, projected through the prism of earlier dis-courses, of polite, civic-minded people going about theirbusiness in ways that enabled self-interest and the com-mon good to coexist in the same sentence, a har-monielehren that could be both realistic and hopeful. Itwas a delicate balancing act, one that Hirschmanclaimed had served a normative purpose of restrainingimpassioned rulers and the ruled, a purpose that hadbeen degraded by what would subsequently happen tothe language of capitalism—and at its extremes, bydespots like Pinochet who claimed to be its last defense.

While the book was greeted with rave reviews, andthe reception and attention delighted Hirschman, at adeeper level the book only magnified the gap betweenhis understanding of the economy and prevailing trendsin the economy. To make matters worse, though he hadretreated to earlier centuries, the crisis of the 1970s washard upon him. Geertz and Hirschman redirected theconcerns of the School of Social Science away from thestrong focus on developing societies to address, startingin 1977, advanced industrial societies. For the first time,European social scientists like Alessandro Pizzorno andClaus Offe came to the School. Also, America’s leadingliberal philosopher, John Rawls, joined the assembly forone semester. The group decided to meet Mondayevenings in people’s homes for informal discussions thatsoon swelled, nurtured by the growing crisis of the wel-fare state, spreading strikes, and the meltdown of New

8

Albert O. Hirschman’s Early Institute Years

Hirschman believed that the dividebetween hope and hopelessness,

optimism and pessimism, was a falseone. It was not a matter of whether

the overall story was bleak or uplifting,but how it was told, for the epic

passage of social change was riddledwith chance and choice.

Albert Hirschman came to the Institute in 1974 and helped create the School of Social Science.

MARTIN

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York City’s finances to address the hot topic of the “gov-ernability of modern democracy.” Rawls and Offe led anevening’s discussion of Habermas’s Legitimation Crisis;another evening Hirschman and Pizzorno led the discus-sion of Mancur Olson’s The Logic of Collective Action.

Having diagrammed his views of original argumentsfor capitalism before its triumph, Hirschman sat down tosettle scores with Olson’s highly influential 1965 work, anear-biblical argument for a model of capitalism after itstriumph. More than any other, Olson’s book nurturedthe emerging field of institutional economics and popu-larized coinages like “collective action problems” and“free-riders.” At the heart of Olson’s work was an argu-ment that modern societies create incentive systemsthat induce individuals to invest their energies in pri-vate goods, but thwart the pooling of these efforts col-lectively to create public goods. Moreover, thesepropensities were bound by an immutable “logic.”Hirschman felt compelled to position himself before tri-umphal discourses of the 1970s, and he took advantageof one evening’s discussion at Geertz’s house to takeOlson as Exhibit A for what he would spend the next fif-teen years trying to expose: the rhetoric and politics ofthe ideological underpinnings of the Right.

It was a heated evening discussion. Geertz found thewhole Olsonian proposition absurd and huffed inobjection to free-riding. Hirschman labored to explainprinciples he disavowed. Rawls retreated into silence.And Herbert Gintis, a visitor from the University ofMassachusetts, insisted that there had to be “an answer”to the Olsonian formula. In the end, Hirschman man-

aged to conclude with one of his favorite quotes fromRousseau: “What makes for human misery is the contra-diction between man and citizen; make him one and youwill make him as happy as he can be; give him wholly tothe state or leave him wholly to himself; but if you dividehis heart you will tear it apart.” The discussion thatevening opened a thickening file, a quest for an “answer”to the vexing question: Was there a way to imagine mod-ern societies consisting of citizens and consumers whowere not forced, or asked, to divide their hearts?

Hirschman’s concern to reconcile the widening gulfbetween public citizenry and private consumers was alsothe result of his irritation with “singular” ways of think-ing and the pernicious ways in which singular thinkingwas shaping world events. In the autumn of 1979, Amer-ican television screens were flooded with scenes fromTehran, where radical students had seized the U.S.embassy. That Thanksgiving, Albert and his wife Sarahinvited some friends over, Roberto Schwarz and CarlosFuentes and their wives, for goose (the Hirschmans’favorite fowl). They were riveted to the television andworried about the government’s response with the elec-tions looming. The images of crowds “seemingly so full ofhatred against the United States,” was utterly depressingfrom Hirschman’s perspective. It was not just the hatredon display in Iran, it was the sense of “unity” in America,and portents of a “turn inward,” that prompted him toobserve, “This may well be the end of public interest indevelopment in the Third World—so, from the point ofview of my interests, I also see it as the end of an epoch.”

Several weeks later, he walked before the podium inDodds Auditorium at Princeton University to deliver theJaneway Lectures to large crowds of students and facultyon the theme of “Private and Public Happiness: Pursuitsand Disappointments.” For Hirschman there was nobasic choice between the two types of happiness; it wasnot “or” that conjoined public to private. If there was achoice, the point of the lectures was to argue that peoplewere always choosing depending on their moods andinclinations, and it was this activity that Hirschmanwanted to draw out. Hirschman’s Janeway Lecturesaddressed experiences and emotional responses to them—

anger at educational institutions, self-incrimination forbuying a large house and regretting it (“buyer’s remorse”),and the ever disappointing “driving experience,” which,far from yielding to the lyrical joy ride, more oftenplunged the BMW-driving pleasure-seeker into trafficjams and car payments. Pursuits of happiness wherever itwas being dispensed left trails of disappointment.

In contrast to Olson’s “logic,” Hirschman presenteda “dialectic” that unfolds within the self, a self com-prised of a complex amalgam of drives. Hirschman’spendular dialectic was the theme of Shifting Involve-ments: Private Interest and Public Action (Princeton Uni-versity Press, 1982), in which he stuck his neck out toformulate an alternative to the gathering political andintellectual orthodoxy. “I have rarely felt so uncertainabout a product of mine,” he told his daughter Katia.“Perhaps this is because, as I say in the preface, what Ihave written is less a work of social science, than theconceptual outline of one or several novels.” Indeed,the preface suggests that there is much more ofHirschman’s personal philosophy and life story stirredinto the prose. It threatened to become a bildungsroman“with, as always in novels, a number of autobiographicaltouches mixed in here and there.”

If there were autobiographical touches, they were notso easy to see. Certainly, no reviewer picked them out,though many did pick on the book as a disappointingone. Compared to earlier books this one was a flop.Nowadays, it is often overshadowed. But one might readShifting Involvements as a resistance against ideas of tri-umphalism of any one side and defeatism of any other.To both he insisted there was always more choice, therewere always more possibilities, always hope. n

9

Jeremy Adelman, a Member (2001–02) in the School ofHistorical Studies, is the Walter Samuel Carpenter IIIProfessor in Spanish Civilization and Culture at PrincetonUniversity, where he is currently the Director of the Coun-cil for International Teaching and Research. At present,he is completing a biography of Albert O. Hirschman,Professor Emeritus in the School of Social Science.

Frank Gehry: Thinking Out Loud

The architect Frank O. Gehry gave a public lecture, “Thinking Out Loud,” at the Institute in March, in which he spoke aboutthe origins and influences of his work. Gehry was a Visitor in the School of Natural Sciences’ Simons Center for Systems Biol-ogy in the spring. He participated in a series of programs at the Institute that explored the relationship between architecture andscience, specifically the process of creativity and research in the two fields. Gehry’s visit was organized by Arnold Levine, Pro-fessor in the School of Natural Sciences, and Irving Lavin, Professor Emeritus in the School of Historical Studies.

PRE-ORDE R RE M I N DE R

A Community of Scholars:Impressions of the Institute for

Advanced Study

In fall 2011, Princeton University Press willpublish A Community of Scholars: Impressions

of the Institute for Advanced Study with photo-graphs by Serge J-F. Levy, a collection of essaysand photographs that captures acad emic andsocial life at the Institute. The volume, withan introduction by Peter Goddard, includesphotographs taken by Levy during the 2009–10academic year and personal reflections byMichael Atiyah, Chantal David, FreemanDyson, Jane F. Fulcher, Barbara Kowalzig,Wolf Lepenies, Paul Moravec, Joan WallachScott, and David H. Weinberg. To pre-ordercopies of the book for $19.95 (a 20 percentdiscount off the $24.95 cover price), pleasecall (800) 777-4726. The ISBN number is978-0-691-15136-6 and the offer code is P04657.The pre-order offer is good until September30, 2011. n

John F. Nash Jr. reads at teatime in this photograph froma book about the Institute forthcoming in fall 2011.

SERGE J -F. LEVY

BENTLEY D

REZNER

From its earliest days, the Institute recognized the im-portance of land and location to its ultimate success.

In considering the acquisition of land, the founders fo-cused on locating the Institute in an area with ready ac-cess to a world-class library, proximity to otherinstitutions of learning, and the opportunity for furtherexpansion to promote institutional atmosphere and spirit.After much discussion, the Buildings and Grounds Com-mittee determined that the Princeton vicinity would beideal because of the opportunity for social and scholarlycontacts and access to university surroundings.

Oswald Veblen, a Norwegian-American topologistwho was a faculty member at Princeton University fortwenty-seven years before becoming the first member ofthe Institute Faculty (1932–60), was instrumental in theInstitute’s acquisition of land in Princeton.When he first learned of the Institute in anannouncement in the New York Times in1930, Veblen wrote to the Founding Direc-tor, Abraham Flexner, suggesting that thenew Institute should be located in the bor-ough or township of Princeton “so that youcould use some of the facilities of the Uni-versity and we could have the benefit ofyour presence.”

Flexner took Veblen’s suggestion underconsideration, and in October 1932, hewrote: “I have it in mind now to go down toPrinceton quietly for a week or so for thepurpose of familiarizing myself with the gen-eral situation, for that may help us in ourfinal choice. I should like to be away fromundergraduate activities and close to gradu-ate activities.”

In 1934, Veblen wrote to Flexner, stress-ing the importance of purchasing more landthan might be deemed necessary and saying,“There is no educational institution in theUnited States which has not in the begin-ning made the mistake of acquiring too littlerather than too much land.”

It took more than five years from theInstitute’s founding for a decision to be madeto locate the Institute on Olden Farm, near aQuaker meeting house on a settlementknown as Stony Brook in Princeton. Flexnerwas initially opposed to the purchase of theproperty, saying, “I am quite clear that at thismoment we have neither the time nor themoney to bother about the Olden Manor andthe Olden Farm . . . . It is my conviction thatwe will never have any academic buildingson the farm, and I have such grave doubts asto the use of the Manor for social purposes . . . .”

By 1936, 256 acres had been purchased for a total of$290,000, including the two-hundred-acre Olden Farm,with Olden Manor—the former home of William Oldenand the residence of the Institute’s Director since 1940—as well as a large, working barn. Veblen continued toexplore local land for sale, and over the next few years hebargained with local landowners to help the Instituteacquire a total of 610 acres, including the Institute Woods.

In 1936, the Buildings and Grounds Committeereported to the Board of Trustees that they had purchaseda “substantial acreage in Princeton” adequate for anyimmediate and future needs. Nine years later, with thepurchase of the Maxwell estate under Frank Aydelotte,Director of the Institute from 1939 to 1947, the Institute’sland acquisition was completed. Aydelotte wrote to Her-bert H. Maass, an Institute Trustee: “I think this is thepsychological moment to close the deal. With this tract inour possession, the Institute will have one of the finestpieces of educational real estate that I know of anywhere.”

The Village Green Today, many of the Institute’s permanent Faculty andthe Members and their families who visit the Institute

each year live on or very close to campus, creating asense of community that fosters serendipitous interac-tions and incidental discussions from which importantinsights often follow. In the development of its campus,members of the Institute’s Buildings and Grounds Com-mittee made it a priority to provide local housing for theMembers and a large proportion of the Faculty to allowfor the cultivation of ideas in a true academic village.

By the end of 1936, there existed throughout Prince-ton a significant shortage of available housing, and whatlittle was available was also very expensive. The Insti-tute turned to Swarthmore College and Princeton Uni-versity to examine how they used part of theirendowment to build rental housing for faculty. In early1937, the Institute’s Board determined that it was essen-

tial that everything possible be done to assist Faculty inacquiring nearby homes. A plan was devised by WinfieldRiefler, Professor (1935–49) in the School of Economicsand Politics (it became part of the School of HistoricalStudies in 1949), that involved the Institute’s sale ofland that was not essential for its main campus to thoseFaculty who wished to erect homes for their own occu-pancy. The Institute hired an architectural firm toreview and identify sites on Olden Farm for the purposeof providing housing to Faculty. Subsequently, BattleRoad Circle was designed and built, with roads and Fac-ulty housing completed before Fuld Hall constructionwas finished. Over the years, the Institute has continuedto develop its land mindful of the need to be able to pro-vide adequate housing for its Faculty. In the near future,the Institute plans to build additional Faculty homes onits campus so as to preserve its fundamental character asa residential institution.

As time went by and the Institute grew, the need fordesignated Member housing located close to the Insti-tute became apparent. In 1941, the Board of Trusteesbegan investigating the option of building apartmentsfor visiting scholars. The urgency of the need called forquick action. Unfortunately, building during wartime

was impossible, and the Institute looked into the possi-bility of prefabricated housing. It took until 1946 beforefirm plans were set to erect dwellings consisting of foursix-family units and seven two-family units betweenCook and Goodman Roads. Julian Bigelow, Member inthe Electronic Computer Project and later the Schools ofMathematics and Natural Sciences, offered to negotiateon behalf of the Institute with the Federal Public Hous-ing Authority for surplus government housing that couldbe made available to educational institutions. Aydelotte,who filed the application for the housing, stressed theexcellent quality of these buildings, which were not pre-fabricated but individually constructed at Mineville,New York, on the edge of the Adirondacks. WithBigelow’s guidance, the Institute was able to purchase

eleven buildings containing thirty-eightapartments of two and three bedrooms each.These apartments were substantially built,with hardwood floors, insulation, storm win-dows, fly screens, clothes lines, and garbagepails, lacking only electric refrigerators.With the assistance of an Institute Trustee,Lessing J. Rosenwald, who was Chairman ofSears, Roebuck and Co., the Institute wasable to secure thirty-eight electric refrigera-tors from Sears. The housing units were“panelized” for transportation to Princeton,and they were occupied in early 1947.

However, by 1957 the limitations of theMember housing, heated by coal stoves thatrequired constant stoking during the longNew Jersey winters, was apparent to J. RobertOppenheimer, Director of the Institute from1947 to 1966. He hired the noted architectMarcel Breuer to design a complex of Memberhousing more appropriate to the community.According to an article in Architectural Recordin March 1968, one of the important factorsin planning the arrangement of the plot wasthe provision of an environment and facilitiesto foster the community spirit of the Mem-bership. The focus was on the “village green,”with the natural configuration and characterof the land being maintained and the place-ment of buildings fit to the existing contoursof the land. Open House Day was held onOctober 11, 1957, offering tours of the newBreuer apartments to the Princeton commu-nity. The Breuer design was so successful thatthe Institute found only very minor changeswere needed when the housing was expandedin 1968, and again in 1973 and 2000.

A Refuge for Ideas and Wildlife The Institute was conceived as a refuge for ideas, but italso serves as a refuge for wildlife. Veblen, who arrived inPrinceton in 1905, loved the outdoors and played aninstrumental role in acquiring the Institute Woods, nowa 589-acre nature reserve that forms a key link in a net-work of green spaces in central New Jersey. In additionto serving on the Buildings and Grounds Committee,Veblen “organized what was called a wood-choppinggroup,” according to Deane Montgomery, the late Pro-fessor (1951–92) in the School of Mathematics. “Theyused to go out and clear some of the paths that nobodyhad cleared at that time.” Veblen was joined by manynotable figures, including the distinguished physicistPaul Dirac, a frequent Member in the School of NaturalSciences between 1934 and 1963. “No one will everknow how many problems in mathematics, physics, his-tory, astronomy, economics, political science, social sci-ence, computing, and biology have been brought onestep closer to a solution by a shared conversation or asolitary walk in the Institute Woods,” wrote GeorgeDyson, a former Director’s Visitor (2002–03) and son ofFreeman Dyson, Professor Emeritus in the School ofNatural Sciences, in the Institute Letter (Winter 2007).

10

The Institute Lands: Cultivating a True Academic Village

Top, an aerial view of the IAS campus taken in 2005 by David Kennedy, a former Member(1986–87, 2004) and Visitor (2005) in the School of Historical Studies. Bottom, a 1946drawing of proposed housing.

DAVID

KENNEDY

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The Institute’s preservation of the woods, farmlands, and surrounding lands wasundertaken with the leadership of the late Princeton resident Frank E. Taplin Jr., Insti-tute Trustee and Trustee Emeritus for more than thirty years. The preservation was doneas part of the 1997 Greenacres easement that unified nearby preserved lands, furtherprotecting a fifty-six-mile-long greenway network through central New Jersey that iscritical for the feeding and nesting of two hundred species of birds on the Atlantic fly-way. With the assistance of dedicated donors, the Institute funds the maintenance ofthe Institute Woods and farmlands, which are utilized year-round by the public. In2008, local residents Addie and Harold Broitman, Friends of the Institute since 1994,made a generous gift through the Broitman Foundation to support trail maintenance forthe benefit of all who use the Woods.

Over the decades the Institute has provided land to help establish the nearby Prince-ton Battlefield State Park. In the early 1950s, the Institute leased land to the State toincrease the size of the park, and in 1973, it conveyed thirty-two acres to the State toenlarge the size of the park by 60 percent. In 1959, the Institute donated the formerMercer Manor monumental portico that now stands on the Battlefield north of MercerRoad, commemorating the common grave of unknown American and British soldierskilled in the Battle of Princeton in 1777.

From its earliest days, the Institute has sought to cultivate a sense of community andcuriosity that extends beyond its campus. Every year, the Institute offers free lectures and concerts to the public, who may also meander the same grounds that have provideda place for contemplation and discussion for generations of Institute scholars fromVeblen and Einstein onward. n

11

An Institute Woods ExhibitionA selection of photographs taken in theInstitute Woods by Vladimir Voevodsky,Professor in the School of Mathematics,will be on display October 24–December 2at the Johnson Education Center of D&RGreenway Land Trust. The photographswill be part of an exhibit of art and photog-raphy highlighting lands protected byD&R Greenway in the Princeton area.The Institute Woods, which comprise589 acres of woods, wetlands, and farm-land, have been permanently conservedsince 1997. An opening reception forthe exhibit will be held November 6from 4 to 6 p.m. at the Johnson Educa-tion Center, located at 1 PreservationPlace, Princeton, New Jersey. For moreinformation, visit www.drgreenway.orgor call (609) 924-4646.

BY DANIELA L. CAGLIOTI

The security of a nation and the safety of its population versus theprotection of constitutional liberties and human rights is a

quandary that arose in the aftermath of 9/11, but it is not novel to thetwenty-first century. Discrimination between citizens and aliens, eth-nicization of citizenship, the use of emergency powers in order to dealwith the enemy and bypass the constitution, and the tendency to shiftguilt and responsibility from the individual to a collective category(e.g., the Jews, the Muslims, etc.) are practices rooted in the past.

In my research, I have been looking at how governments andarmies during World War I began to deal with these issues. The gov-ernments of almost all the nations that took part in World War Iissued decrees and implemented measures against civilians of enemynationalities who at the outbreak of the war were within their terri-tory. Persons with ties to an enemy country were presumed to be moreloyal to their origins than to the countries in which they worked andlived. German and Austro-Hungarian subjects living in France,Britain, or Russia, and later in all the countries that joined the Allies,and British, French, and Russian citizens who lived in Germany or inthe Habsburg Empire, and then in Turkey or Bulgaria, were recast asdangerous, sometimes extremely dangerous, internal enemies.

Individuals with connections to enemy countries were in somecases passing through as tourists, students, or seasonal workers, but in most cases, theyhad been residents of the country for many years. Some of them were born in the coun-try, some had married a national, others had acquired nationality papers, others were inthe process of getting them. Many owned houses, land, or firms and spoke the local lan-guage. The outbreak of the war transformed them––independently of their personalstory, feelings, ideas, and sense of belonging––into enemy aliens, accused of posing athreat to national security and the survival of each country.

During World War I, government leaders (and sometimes armies) assumed full legisla-tive powers and issued orders in council or decrees that limited personal freedom; restrict-ed civil and political liberties; and eventually curbed the economic activities of thecivilians of enemy nationality and jeopardized their property rights. Enemy civilians wererequired to register; abandon their homes in order to live in designated areas; not own cars,bicycles, and other means of transport or communication, like carrier pigeons or telegraphs;and submit to curfews. Each country adopted a combination of expulsion, repatriation, dis-placement, and, above all, internment of enemy nationals. Concentration camps openedalmost everywhere, in Europe, in the United States, in Brazil, in the Dominions of theBritish Empire, and in the colonies.

Enemy aliens were prohibited from taking part in assemblies and demonstrations, own-ing newspapers and magazines or writing for them, and meeting in ethnic clubs and soci-eties. In many countries ethnic presses were closed down, and the teaching of enemyforeign languages in schools was suspended. Many, trying to elude the severity of therestrictions, changed their surnames and hid their origins. Even music composed by musi-cians originating from enemy countries could not be played, and concert halls and opera

houses had to switch to a different repertoire.Almost all the countries at war issued a “trading with the enemy

act,” which prevented enemy aliens from continuing their businessactivities. These acts ordered the seizure, confiscation, and some-times the liquidation of patrimonies, shops, firms, shares and assets,patents, and copyright.

Passports and nationality papers proved to be less powerful thanorigins in defining national identity. Denaturalization (and conse-quently disenfranchisement) emerged as a common practice inFrance, Britain, Germany, and Canada, while a ban on new natu-ralizations was established almost everywhere.

As the war went on, the campaign against enemy aliens extend-ed well beyond individuals who had originated from an enemy coun-try. The loyalty of groups of citizens was questioned based on ethnicorigin, religious belief, or former nationality. Among those affectedwere people who had recently acquired nationality papers (for exam-ple, the Ruthenians of the Habsburg Empire who had migrated toCanada or Germans in France who very recently had acquired citi-zenship); women who had lost their original citizenship and acquireda new one by the way of a marriage; minorities who had nationalaspirations (the Armenians or the Greeks in the Ottoman Empire,the Poles, Czechs, Italians, etc., in the Austro-Hungarian Empire);minorities who were resilient to forced nationalization and had longbeen discriminated against (the Jews almost everywhere; the Mus-

lims in the Russian Empire); and minorities living in border regions whose loyalty was con-sidered difficult to ascertain (the Alsatians and Lorrainians in France, the Italians ofTrentino, South Tyrol, and Istria, etc.).

Popular reaction to the government policies took many forms: complaints, informing,reporting, acts of vandalism against properties occupied by enemy aliens (shop-windowsmashing, the pillaging and burning of shops and houses belonging to alleged enemyaliens), verbal violence, the hunting and lynching of supposed spies and enemies on thestreets or fits of public and collective hysteria. The press fueled the anti-alien feelings witharticles, cartoons, pamphlets, and campaigns of racial hatred. Pacifist and liberal groupsalmost everywhere had difficulties voicing their opposition to such behavior.

During the Great War, juridical measures, internment, violence, and anti-alien behav-ior contributed to the destruction or dispersal of many ethnic groups, altering the ethnic,social, and linguistic composition of many cities and regions in Europe and elsewhere. Thecampaign against enemy aliens also promoted a nationalization of economies, both byexpelling foreign capital and presence and by increasing state control, thus laying the frame-work for developments in the decades that followed. The obsession for security justified vio-lence and violations of international law, while resorting to the use of collective categoryprevented for many decades the emergence of a language and practice of human rights. n

Security Versus Civil Liberties and Human Rights

Daniela L. Caglioti, the Elizabeth and J. Richardson Dilworth Fellow in the School ofHistorical Studies (2011), is a modern sociopolitical historian and Associate Professor atUniversità degli Studi di Napoli Federico II.

VLADIM

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OEVODSKY

A memo from the Institute archives explaining theprocess of reclaiming a camera seized duringWorld War II from Shizuo Kakutani, Member inthe School of Mathematics from 1940–42

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The Association of Members of the Institute for AdvancedStudy (AMIAS), founded in 1974, supports the work

of the Institute and promotes interaction between the Instituteand the academic community at large. At the November 2010annual meeting of AMIAS, five new Trustees were elected tothe sixteen-person Board that governs AMIAS, which com-prises some six thousand current and former Members, Visi-tors, and Research Assistants.

Most scholars and scientists come to the Institute with afocused initiative, but often their experiences are expansive,sometimes even transformative. Below, the five newly elect-ed Board members recall their time at the Institute and reflecton its influence.

— n —

For me, being a Member of the School of HistoricalStudies in 2002–03 was the best sort of retreat. I had

been working on my second book, Romulus’ Asylum:Roman Identities from the Age of Alexander to the Age ofHadrian, for five or six years when I came to the Institute,writing bits of drafts in between everything else one doesin a demanding academic position. I finished my book atIAS, and spent many hours reading and writing in anarmchair in the lower floor of the library, looking outonto the small lake. I remember it as mostly frozen andsnow-covered: it was a hard winter. I loved being amongstpeople who were completely dedicated to whatever it wasthey were working on, but who didn’t take themselvestoo seriously: I think that this modesty is one of the fea-tures of the IAS community that I most prize. I also reallyappreciated that one could choose to share one’s ideas, orindeed not share them (sometimes, one just needs to gointo a zone to start having ideas), in many different for-mats: over lunch, in more or less formal workshops (suchas our wonderful “Empires” workshop), or at one of theweekly colloquia. I loved my position at Birkbeck Col-lege, University of London, but it was very hard to goback to reality, and ultimately the IAS year left me eagerfor new challenges and new experiences: in January 2007,I moved to Harvard. I’m so grateful for all the opportuni-ties that my year at IAS gave me, and not least for thewonderful friends I made in that time. —Emma Dench, Professor of the Classics and of History, HarvardUniversity; Member, School of Historical Studies, 2002–03

— n —

The time I spent at the School of Social Science was aninvaluable intellectual and professional experience.

As a junior scholar, my immersion in the rich, interdisci-plinary environment at IAS definitively shaped the sub-sequent course of my academic career. First, I had the timeand resources necessary to finish writing my second book,a project that benefited from the immense generosity, crit-ical guidance, and practical feedback of other Members.Many of these colleagues were not only insightful inter-locutors but also became dear friends, with whom I stillmaintain contact to this day. Second, as a single mother,having access to the exceptional childcare at Crossroads

was absolutely vital in giving me the peace of mind nec-essary to concentrate on my research and produce thequality of scholarship necessary to achieve tenure. Mostimportantly, I had the opportunity to work together withProfessor Joan Scott. The chance to share arguments andideas with her was like drinking a bucket of cerebral Mir-acle-Gro. Professor Scott’s selflessness as a mentor en-couraged me to push myself beyond my theoreticalcomfort zones and to challenge prevailing paradigms, skillsthat continue to enrich all of my scholarly work and forwhich I am deeply grateful.

—Kristen Ghodsee, John S. Osterweis Associate Professor of Gender and Women’s Studies, Bowdoin College;

Member, School of Social Science, 2006–07

— n —

Iremember fondly the two years I spent at IAS workingwith Steve Adler on the experimental implications of

unified field theories of elementary particle interactions.We also tackled a very hard problem that still is un-solved—how to reconcile general relativity with quan-tum field theory. I especially enjoyed the Institute’s rich,intellectually stimulating environment and many intensediscussions with Members across disciplines at lunch orat tea or evening dinners. I have spent my life in elite in-stitutions and it’s fair to say that none has come close toproviding the intellectually engaging atmosphere thatI cherished at the Institute. Although my work at theInstitute was productive (seven research papers came outof it), while there I decided to abandon physics to dowork that was more down-to-earth, which could more di-rectly contribute to human well-being.

During a walk in the Institute Woods with a friend, Idecided that I didn’t want to spend the rest of my life alonein an office grappling with a few equations. My decision togo to medical school to become a physician scientist led toa very different life, but it’s also been very gratifying.

—Judy Lieberman, Senior Investigator, Immune DiseaseInstitute and Program in Cellular and Molecular Medicine,Children’s Hospital Boston; Professor of Pediatrics, Harvard

Medical School; Member, School of Natural Sciences, 1974–76

— n —

Iwas at the Institute for the academic year 1971–72 asResearch Assistant to Clifford Geertz. This was prior

to the establishment of the School of Social Science in1973, so the number of social scientists was only a hand-ful, including myself, the only junior member. I learned agreat deal during that year, particularly from CliffordGeertz and David Riesman, both of whom were excep-tionally generous and inspiring mentors. Equally impor-tant was my interaction with other Members, and inparticular a group of young physicists with whom I en-gaged in a wide-ranging cross-disciplinary dialogue overlunch on most days. In my experience, the Institute trulylived up to its reputation as a haven for complete intel-lectual liberty. Shortly after my stay at the Institute, I leftthe academic world to pursue a career in finance, which

resulted in overseas assignments for some thirty years. Inthe business world, the words “academic” and “intellec-tual” have negative connotations, and I was often advisedby search consultants not to include my year at the Insti-tute on my CV, but I always insisted on keeping it there.In my mind, the year I spent at the Institute was amajor factor in my success in the business world. Uponretirement in 2006, I returned to live in Princeton,partly because of the attraction of the Institute.

—Fouad J. Masrieh, Research Assistant, School of Social Science, 1971–72

— n —

Ihave spent three periods of time in residency at IAS,and I am looking forward to a fourth in the spring of

2012. In 1979–80, one of the first special years in math-ematics at IAS took place, organized by S. T. Yau, whoshortly afterwards received a Fields Medal and became apermanent member of the mathematics Faculty. The yearwas full of activities: we had an eating group, playedvolleyball, and took part in at least three active ongoingseminars. I had spent two years (during the Vietnam War)at U. C. Berkeley, but since then had not been in themidst of the relatively new field of applying partial dif-ferential equations to geometry. The year at IAS allowed meto take part in this development and to form the collab-orations that were essential to the next decade of my ca-reer. This has been an exciting area of mathematics;the privilege I have had of working in it is partly due tothis year at IAS. I returned in 1995 for the fall term,which was a good experience, but too short. I particularlyenjoyed meeting Members from other Schools at lunchand tea, and I found it a great place to work, espec iallyto write up material I had worked on for several years. Iwas then invited to organize a special year in 1997–98,in which I tried to connect researchers working on thealgebraic aspects of partial differential equations withthose working on more analytic estimates. This is theshadow of difficulty that also exists in theoretical physics.This is a long-term project of mine, which I don’t think hasled where I would like to see it go. I hope that I was able toencourage the younger Members, as I had been encouragedeighteen years before. If I have any regrets, it is that I didnot spend enough time in contact with Members of otherdisciplines. I hope to remedy this in the spring of 2012.

—Karen K. Uhlenbeck, Professor of Mathematics and Sid W. Richardson Regents Chair, University of Texas, Austin;Member, School of Mathematics, 1979–80, 1995, 1997–98

12

New AMIAS Board Members Reflect on Institute’s Influence

AM IAS LECTURE — NOVE M BE R 11, 2011

Objectivity: The Limits of Scientific Sight

As part of the annual.meeting of the Association of Members of the. Institute for Advanced Study to be held on November 11, Peter

Galison, Joseph Pellegrino University Professor at Harvard Universityand a former Institute Trustee, will give a public lecture, “Objectivity:The Limits of Scientific Sight.” Galison will discuss the evolution andlimits of objectivity and how reproduction of images has begun to cedeto something more directly productive of new objects—presentationinstead of representation. The lecture will take place at 5:00 p.m. inWolfensohn Hall. For more information, contact amias@ias.edu orLinda Cooper at (609) 734-8259.

Peter Galison

While the Insti-tute welcomes

gifts of any amount,some former IASscholars find that theyare able to make giftsof a larger size. Suchcontributions have asignificant impact onthe Institute’s abilityto fund its programsand, in particular, thework of current Mem-bers. To recognize this

exceptional support from its former Members andVisitors, the Institute has created three leadershipgiving categories, the Flexner, Aydelotte, and Op-penheimer Circles, with benefits offered at eachlevel. All Circles’ donors are recognized for theirgenerosity with a specially designed bookplate inan IAS library book whose purchase has been fa-cilitated in part by the donation. Stephen V. Tracyand June W. Allison are among the foundingmembers of the Oppenheimer Circle. For more in-formation about the Circles opportunities, visitwww.ias.edu/people/amias.

CORY W

EAVER

BY LINDA G. ARNTZENIUS

The above photograph (ca. 1958) of Marston Morse(1892–1977), Professor in the School of Mathemat-

ics, and his wife Louise is a rare image from one of two al-bums compiled by Louise Morse over seven decades. It isunusual in that it includes Louise herself. Louise wasoften the one behind rather than in front of the camera.Her two packed volumes reveal the Institute’s mathe-matical community at leisure. Enhanced with newspaperclippings and carefully annotated with names and dates,the albums, which have been promised to the ShelbyWhite and Leon Levy Archives Center, are a treasuretrove of snapshots taken at the annual gatherings ofInstitute Faculty, Members, Visitors, and their familiesheld by Marston and Louise in their home.

Marston and Louise Morse were known as generousand engaging hosts, inviting groups of twenty mathe-maticians at a time on four separate occasions through-out the year. Louise made a point of knowing the nameof every guest so that she could introduce newcomers.After her husband’s death, she continued the traditionwith annual parties that coincided with the annualMarston Morse Lectures each spring.

The couple met mid-Atlantic in 1936 when Marstonspotted Louise and her three friends dancing onboardship. He had joined the Faculty of the Institute forAdvanced Study the year before, taking his place along-side James W. Alexander, Albert Einstein, OswaldVeblen, John von Neumann, and Hermann Weyl. Bornin Waterville, Maine, Morse was a talented pianist whohad to choose between a career in music or mathematics.He is recognized for defining a new branch of mathemat-ics (differential topology) known as Morse theory. In1936, he was on his way to Europe to lecture in mathe-matics. Louise, who grew up in Hanging Rock, Ohio, hadjust graduated in nursing from Johns Hopkins and wastaking a six-week trip with her friends. Although Morsewas a good deal her senior, she accepted his invitation todance. They were married in 1940 (she was twenty-eight,he was forty-seven), and took up residence at 40 Battle

Road—which became a second home to those mathe-maticians from around the world visiting the Institute.

A cherished member of the Institute community,Louise celebrated her one hundredth birthday in June.Her memories reach back to teas with Elizabeth Veblen,cocktails with the von Neumanns, and dinners with theOppenheimers at Olden Farm. Shortly after her marriage,she found herself seated next to Albert Einstein at a din-ner hosted by Abraham Flexner and his wife Anne Craw-ford Flexner in New York City. Although Einstein jokedthat he didn’t know what to say to a new young bride, itwas Louise who recalls being at a loss for words. Later sheand Einstein would share a common cause in deploringthe unequal treatment of African Americans in Americaand in Princeton. Louise is well-known as a loyal sup-porter of the Princeton Committee of the NAACP LegalDefense and Educational Fund, which paid tribute to hercontributions and commitment last October.

In May, Louise donated a first edition of AbrahamFlexner’s autobiography I Remember to the Shelby

White and Leon Levy Archives Center. Louise pastedvarious personal mementos into the book, includingpersonal correspondence between the Flexners and theMorses between 1940 and 1956. The book is inscribedby the author in honor of the birth of Louise andMarston’s daughter Julia. n

13

In 2010–11, gifts provided by the Friends of theInstitute for Advanced Study reached an all-timehigh, with $771,000 raised against a $750,000goal. Members of the Friends Executive Commit-tee gathered with Director Peter Goddard (center)at the annual meeting of the Friends in May.Friends play a vital role in Institute life, linking itto the broader community, acting as informedambassadors for the work conducted at the Insti-tute, and helping to maintain the Institute’s finan-cial independence through their generous annualcontributions. For more information about theFriends, please visit www.ias.edu/people/friendsor contact Pamela Hughes at (609) 734-8204 orphughes@ias.edu.

The first Institute Faculty recognized that a strong,working library was critical to the work of the

Institute. Books were purchased as early as 1934, fiveyears before the opening of Fuld Hall. The volumes weredesignated with an Institute bookplate and placed inthe Princeton University Library for the Humanitiesand Fine Hall Mathematics Library to be used by bothcommunities.

Faculty members acted as purchasing agents for bookand journal acquisitions. Benjamin Meritt, the firstProfessor in the School of Humanistic Studies (a pre-cursor with the School of Economics and Politics of thecurrent School of Historical Studies) set up a workingepigraphical library, built the Institute’s collection ofsqueeze inscriptions in the 1930s (see the Institute Let-ter, Fall 2010), and arranged for books to be sent fromGreece to 20 Nassau Street, the primary office of theInstitute at the time.

In January 1940, Frank Aydelotte, the Director ofthe Institute, reported to the Board of Trustees thatwithout a library, scholars would be unable to work inFuld Hall and would have to spend more time inPrinceton University’s Fine Hall. Aydelotte estimatedthat the School of Mathematics would need about$40,000 and that the other two Schools—HumanisticStudies and Economics and Politics—would needanother $60,000, equivalent to about $1.5 milliontoday. The “library problem” was solved in 1940,thanks to a gift of $25,000 per year for four years fromthe Institute’s founders, Louis Bamberger and his sisterCaroline Bamberger Fuld. The Institute Library adopt-ed the hours set by Fine Hall’s Mathematical Library,which remained open twenty-four hours a day.

The original Institute Library was located on thesecond floor of Fuld Hall, and it grew steadily, due inpart to donations from Faculty and Members. Amongthese early generous individuals was Hetty Goldman,the first female Professor in the School of HumanisticStudies, who donated her library in 1950. EdwardCapps, an early Member also affiliated with the School,funded the Loeb Classical Library at the Institute andserved as the first American editor of the series. ErnstH. Kantorowicz, a medievalist and a member of theSchool of Historical Studies Faculty, donated his libraryand a small collection of Greek vases. Two foundingProfessors of the School of Mathematics, HermannWeyl, who also served as the first librarian of the Insti-tute, and Oswald Veblen gave books to the Institute in1956 and 1960, respectively. “I am delighted that thelibrary is developing into so active and important a partof the Institute,” Aydelotte wrote to Library AssistantDorothy Halmos in September 1940.

Other notable donations that augmented theLibrary’s collections include a collection of first edi-tions in the history of science and bibliography pre-sented in the 1950s by Lessing J. Rosenwald, Chairmanof Sears, Roebuck and Co. and a Trustee of the Institutefrom 1940 to 1979. The memorial book fund estab-lished in memory of Leon Levy, a Trustee from 1988 to2003, continues to make possible the acquisition of spe-cial collections, particularly in the history of ideas. TheUsdan Fund established by Leo Usdan, who was notaffiliated with the Institute, supports mathematics andsciences. In 1964, the humanities collection moved fromFuld Hall to the newly constructed Historical Studies–Social Science Library designed by Wallace K. Harrisonand built during J. Robert Oppenheimer’s tenure asDirector. The Mathematics–Natural Sciences Libraryand the Historical Studies–Social Science Library con-tinue to develop specialized and selective collectionsunder the guidance of Faculty and Members, providingan important research resource for the Institute com-munity. For more information on the collections, staffcontacts, or to view the desiderata list, please visit thelibraries website, http://library.ias.edu/. n

Record Gifts fromFriends of the Institute

Linda G. Arntzenius, a member of the Institute’sPublic Affairs staff from 2003–06, is the author ofImages of America: Institute for AdvancedStudy (Arcadia Publishing), which is dedicatedto Louise Morse and includes a selection of imagesfrom Louise’s albums.

Contributions to IAS History from Louise Morse

Institute Libraries: A Legacy of Donations

ANDREA K

ANE

Louise’s two packed volumes reveal the Institute’smathematical community at leisure.

COURTESY O

F LOUISE M

ORSE

COURTESY O

F LOUISE M

ORSE

Summer 2011

Have you moved? Please notify us of your change of address. Send changes to: Public Affairs, Institute for Advanced StudyEinstein Drive, Princeton, NJ 08540 or email mailings@ias.edu

Non-Profit Org.U.S. Postage PAIDPermit #49Princeton, NJIASThe Institute Letter Summer 2011

Peter Goddard, Director

FacultyDanielle S. AllenNima Arkani-HamedYve-Alain BoisJean BourgainAngelos Chaniotis Patricia CroneNicola Di CosmoDidier FassinHelmut Hofer Piet HutJonathan IsraelStanislas LeiblerRobert MacPhersonJuan MaldacenaEric S. MaskinPeter SarnakJoan Wallach ScottNathan SeibergThomas SpencerScott TremaineVladimir VoevodskyAvi WigdersonEdward WittenMatias Zaldarriaga

Faculty EmeritiStephen L. AdlerEnrico BombieriGlen W. BowersockCaroline Walker BynumGiles ConstablePierre Deligne

Freeman J. DysonPeter GoldreichPhillip A. GriffithsChristian HabichtAlbert O. HirschmanRobert P. LanglandsIrving LavinArnold J. LevinePeter ParetHeinrich von StadenMichael WalzerMorton White

Board of TrusteesCharles SimonyiChairmanJeffrey P. BezosVictoria B. BjorklundCurtis CallanCynthia CarrollMario DraghiRoger W. Ferguson, Jr.E. Robert FernholzCarmela Vircillo FranklinPeter Goddard Vartan GregorianJohn S. HendricksPeter R. KannBruce KovnerSpiro J. LatsisMartin L. LeibowitzNancy S. MacMillanDavid F. MarquardtNancy B. PeretsmanMartin Rees

David M. RubensteinJames J. SchiroEric E. SchmidtWilliam H. Sewell, Jr.Harold T. ShapiroJames H. SimonsPeter SvennilsonShelby WhiteMarina v.N. WhitmanAndrew J. WilesBrian F. Wruble

Trustees EmeritiRichard B. BlackMartin A. ChooljianSidney D. DrellRalph E. HansmannHelene L. KaplanImmanuel KohnDavid K.P. LiHamish MaxwellRonaldo H. SchmitzMartin E. SegalMichel L. VaillaudLadislaus von HoffmannJames D. WolfensohnChairman Emeritus

Institute for Advanced StudyEinstein DrivePrinceton, New Jersey 08540(609) 734-8000www.ias.edu

Bla

ck H

oles

and

Qua

ntum

Mec

hani

csIn a paper written in

1939, A

lbert E

instein attempted to

reject th

e no

tion

of b

lack holes th

at his th

eory

of general relativ

ity and

gravity, published more than tw

o decades earlier, seem

ed to

predict. “The essentia

lresult of this investigation,” claimed Einstein, who

at the time was six years in

to his app

ointmen

t as a

Professor at the In

stitute, “is a clear und

erstanding as to why th

e ‘Schwarzschild

singularities’ do not exist

in physical reality.”

Schw

arzschild

singularities, later coined “black holes” b

y John

Wheeler, former M

ember in the Scho

olof M

athe

matics, describe ob

jects that are so massive and

com

pact tha

t time disapp

ears and

space

becomes in

finite. The sa

me year th

at Einstein sought to

discoun

t the existence of b

lack holes, J. R

obert

Oppenheim

er, w

ho would becom

e Director o

f the In

stitute in 1947, and

his student H

artland S. Snyder

used Einstein’s theory of general re

lativity to

show

how

black holes could fo

rm. T

he above pho

to, taken

at th

e Institute in th

e late 1940s, sho

ws O

ppenheim

er with Einstein. A

ccording to

Jeremy Bernstein, a

physicist, author, a

nd fo

rmer M

ember in the

Sch

ool o

f Mathe

matics, it is unk

nown whe

ther Einstein

and Oppenheim

er ever d

iscussed black holes, but neither worked on

the subject a

gain.

In the fo

llowing pages, Juan M

aldacena, P

rofessor in

the Schoo

l of N

atural Sciences, explains the

developm

ent o

f a string

theoretic interpretation

of b

lack holes whe

re quantum

mecha

nics and

gen

eral

relativity, p

reviou

sly considered in

compatible, are united. W

ork by M

aldacena and

others has given a

precise description of a black hole, which is described holograph

ically in

term

s of a th

eory living on the

horizon. A

ccording

to this the

ory, black holes beh

ave lik

e ordina

ry quantum

mecha

nical o

bjects—

inform

ation about them is not lost, as p

reviously thought, but retained on

their h

orizon

s—leading ph

ysi-

cists to lo

ok at black ho

les as la

boratories fo

r describing

the

quantum

mecha

nics of spacetime an

d for

mod

eling strong

ly in

teracting qu

antum sy

stem

s.

IAS

The

Inst

itute

Let

ter TIME & LIFE PICTURES/GETTY IMAGES