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Novos Observáveis Novos Observáveis em em
CosmologiaCosmologiaMiguel QuartinMiguel Quartin
Instituto de FísicaInstituto de FísicaUniv. Federal do Rio de JaneiroUniv. Federal do Rio de Janeiro
Obs. Valongo – Mar 2013Obs. Valongo – Mar 2013
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Dark Energy in 2 slidesDark Energy in 2 slides
Observational evidence for dark energy:Observational evidence for dark energy: Cosmic Background Radiation (CMB) →Cosmic Background Radiation (CMB) → Nobel Prize 2006Nobel Prize 2006 Supernovae →Supernovae → Nobel Prize 2011Nobel Prize 2011 Matter power spectrum in large scale structureMatter power spectrum in large scale structure Age of the Universe > age of oldest starsAge of the Universe > age of oldest stars Baryon Acoustic OscillationsBaryon Acoustic Oscillations
A universe with only A universe with only standard model particlesstandard model particles + + dark dark mattermatter cannot explain cannot explain anyany of the above! of the above!
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Dark Energy in Dark Energy in 2 slides2 slides
N.B.: BAO →N.B.: BAO →Baryon Acoustic Baryon Acoustic Oscillations ↔Oscillations ↔matter power matter power spectrumspectrum
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Distances in CosmologyDistances in Cosmology
Luminosity X Angular X Comoving (radial)Luminosity X Angular X Comoving (radial) Different observations different distances→Different observations different distances→
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Part IPart I
Standard observational Standard observational techniquestechniques
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SupernovaeSupernovaeType Ia SupernovaeType Ia Supernovae
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100
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Type Ia Supernovae (2)Type Ia Supernovae (2)
Standardizable candlesStandardizable candles
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Hubble diagramHubble diagramddLumLum(z)(z)
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Cosmic Microwave Background Cosmic Microwave Background Radiation (CMB)Radiation (CMB)
Oldest photons in the Universe: redshift Oldest photons in the Universe: redshift z ~ 1100z ~ 1100 Nearly-isotropic 2.725 K radiationNearly-isotropic 2.725 K radiation
Anisotropies: ~ 1 part in 10Anisotropies: ~ 1 part in 1055
Temperature of CMB 13.6 eV (ionization of H)↔Temperature of CMB 13.6 eV (ionization of H)↔
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CMB (2)CMB (2) Angular power spectrum ( spher. harmon. decompos.)↔Angular power spectrum ( spher. harmon. decompos.)↔
WMAP 9
ACT
SPT
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CMB (3)CMB (3)
WMAP mission:WMAP mission: Observed the CMB for 9 years;Observed the CMB for 9 years; Reduction of the volume of the 6-dimensional Reduction of the volume of the 6-dimensional ΛΛCDM CDM
parameter space (parameter space (ΩΩb0b0, , ΩΩm0m0, h, A, , h, A, ττ, n, nss) by ) by ~ 68,000~ 68,000
TheThe same model same model still works! still works! Non-trivial statistical result!Non-trivial statistical result!
(Very) near future:(Very) near future: PlanckPlanck Atacama Cosmology Telescope (ACT)Atacama Cosmology Telescope (ACT) South Pole Telescope (SPT)South Pole Telescope (SPT)
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Matter Power Spectrum (linear)Matter Power Spectrum (linear)
Initial conditions Initial conditions (CMB) (CMB)
++ linear linear perturbation perturbation theory theory
small scales
large scales
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Baryon Acoustic OscillationsBaryon Acoustic Oscillations
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Baryon Acoustic Oscillations (2)Baryon Acoustic Oscillations (2)
1515 (dAng
2
dComov
)1/3 (Mpc / h)
Baryon Acoustic Oscillations (3)Baryon Acoustic Oscillations (3)
SDSS (2005)
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Baryon Acoustic Oscillations (4)Baryon Acoustic Oscillations (4)
WiggleZ (2011)
(dAng
2
dComov
)1/3 (Mpc / h)
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Matter Power Spectrum (non-linear)Matter Power Spectrum (non-linear)
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Weak Gravitational LensingWeak Gravitational Lensing
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Part IIPart II
Motivation Motivation to go beyondto go beyond
2020
Precision Cosmology vs.Precision Cosmology vs.Accuracy CosmologyAccuracy Cosmology
Precise parameter estimation in Precise parameter estimation in ΛΛCDM CDM not enoughnot enough Very important to cross-check Very important to cross-check observationsobservations
Rule-out systematicsRule-out systematics Very important to cross-check Very important to cross-check theoretical assumptionstheoretical assumptions
e.g.: homogeneity, isotropye.g.: homogeneity, isotropy
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Dark Energy: the 3-fold way outDark Energy: the 3-fold way out
Usual 2 ways of explaining dark energy:Usual 2 ways of explaining dark energy:
Actually, there is a Actually, there is a thirdthird way out! way out! Keep Einstein theory and “normal” (cold + baryonic) matterKeep Einstein theory and “normal” (cold + baryonic) matter Change the Change the metricmetric
Modified Gravity New fundamental fields
Λ, f(R), f(G), Unimodular, DGP, Horava-Lifshitz, extra dimensions, Einstein-Aether, degravitation, Cardassian, branes, strings...
Quintessence, Quartessence, K-essence, Chaplygin gas, interacting fields, n-Forms,vector fields, Braiding fields...
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Homogeneity and IsotropyHomogeneity and Isotropy The most basic (and old) tenets of cosmologyThe most basic (and old) tenets of cosmology
Friedmann-Lemaître Robertson Walker (FLRW) metric:Friedmann-Lemaître Robertson Walker (FLRW) metric: most general homogeneous and isotropic metricmost general homogeneous and isotropic metric overwhelmingly successful at describing the universe in overwhelmingly successful at describing the universe in
large-scaleslarge-scales ConsistentConsistent with all current observations with all current observations
Hard to probe directly →Hard to probe directly → lightconelightcone vs. vs. const. timeconst. time slices: slices: Possibility Possibility →→ more exotic models may also be more exotic models may also be consistentconsistent
with datawith data e.g.: void models; e.g.: void models; anisotropic models; ...anisotropic models; ...
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Homogeneity?Homogeneity? LTB metric (spher. symmetric, inhomogeneous) Gpc →LTB metric (spher. symmetric, inhomogeneous) Gpc →
Void modelsVoid models
SurprinsinglySurprinsingly successful as an accelerating model without successful as an accelerating model without Dark Energy;Dark Energy;
Can fit all observations in the light cone SNe, BAO & CMBCan fit all observations in the light cone SNe, BAO & CMB But fails for observations inside the light cone (kSZ, But fails for observations inside the light cone (kSZ,
redshift drift & CMB blackbody spectrum)redshift drift & CMB blackbody spectrum)
Quartin, Amendola 0909.4954 (PRD)Caldwell, Stebbins 0711.3459 (PRL)Zhang, Stebbins 1009.3967 (PRL)
Marra, Notari 1102.1015 (CQG)
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Isotropy?Isotropy?
People usually consider People usually consider 2 possible anisotropies2 possible anisotropies ShearShear VorticityVorticity
But there is a 3But there is a 3rdrd type of anisotropy: (spatial) type of anisotropy: (spatial) curvature curvature anisotropyanisotropy Basically: the 3-curvature can be different in different Basically: the 3-curvature can be different in different
directionsdirections There exists aniso. curv. models which areThere exists aniso. curv. models which are
HomogenousHomogenous IrrotationalIrrotational Shear-freeShear-free
Koivisto, Mota, Quartin, Zlosnik 1006.3321 (PRD)
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Void modelsVoid models
Void matter density profileVoid matter density profile
z = 0
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Constraints on Void ModelsConstraints on Void Models
Voids which are too large (> 3 Gpc) are in conflict withVoids which are too large (> 3 Gpc) are in conflict with CMB blackbody spectrum CMB blackbody spectrum
Caldwell & Stebbins: 0711.3459 (PRL) Kinematic Sunyaev-Zeldovich eKinematic Sunyaev-Zeldovich effectffect from large clusters from large clusters
García-Bellido & Haugbolle: 0807.1326 (JCAP) free efree e–– kSZ at small scaleskSZ at small scales
Zhang & Stebbins 1009.3967Zibin & Moss 1105.0909 (CQG)
Recent work:Recent work:Biswas, Notari & Valkenburg
1007.3065Marra & Notari: 1102.1015
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Part IIIPart III
New observational New observational techniquestechniques
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Supernova weak-lensingSupernova weak-lensing
Supernova light travels huge distancesSupernova light travels huge distances Lensing →Lensing → on averageon average no magnification (photon # conser.)→ no magnification (photon # conser.)→
Important quantity magnification PDF (→Important quantity magnification PDF (→ κκPDF)PDF) Zero mean; very skewed (most objects de-magnified)Zero mean; very skewed (most objects de-magnified)
Adds non-gaussian dispersion to the Hubble diagramAdds non-gaussian dispersion to the Hubble diagram
Function of three dAng
(z)
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Supernova Lensing (2)Supernova Lensing (2)
We developed a We developed a fast wayfast way to compute the κ to compute the κPDF PDF based on the Halo-model and Navarro-Frenk-White based on the Halo-model and Navarro-Frenk-White
profilesprofiles accurate when compared to N-body simulationsaccurate when compared to N-body simulations many redshift bins; many redshift bins; different cosmologicaldifferent cosmological parameters parameters
We compute the We compute the first central momentsfirst central moments of of κκPDF for all z's PDF for all z's and all parametersand all parameters Mean (zero); variance; skewness & kurtosisMean (zero); variance; skewness & kurtosis ““Cumulants cumulate” variance; skewness & kurtosis of →Cumulants cumulate” variance; skewness & kurtosis of →
the convolved (final) PDF.the convolved (final) PDF. What's the variance of the variance/skewness/kurtosis?What's the variance of the variance/skewness/kurtosis?
Amendola, Marra & Quartin (in prep)
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Supernova Lensing (2a)Supernova Lensing (2a)
magnificationde-magnif.
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Supernova Lensing (3)Supernova Lensing (3)Amendola, Kainulainen, Marra & Quartin 1002.1232 (PRL)
convolution
supernova
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Hubble diagramHubble diagram
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Supernova Lensing (6)Supernova Lensing (6)
The The non-gaussiannon-gaussian scatterscatter of supernovae in the Hubble of supernovae in the Hubble
diagram will tell us about diagram will tell us about σσ88 up to up to ~1%~1% precision! precision!
Amendola, Marra & Quartin (in prep)
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The Redshift DriftThe Redshift Drift
Even in Even in ΛΛCDM, the redshift CDM, the redshift z z of a source is not constant of a source is not constant
The evolution of The evolution of zz was first estimated by Sandage in was first estimated by Sandage in 1962!1962!
This effect is called This effect is called Redshift-Drift Redshift-Drift (or Sandage effect)(or Sandage effect) Model dependent!Model dependent!
Very accurate spectroscopy can be used to distinguish Very accurate spectroscopy can be used to distinguish between such models.between such models.
Uzan, Clark & Ellis, 0801.0068 (PRL)
Balbi & Quercellini, 0704.2350 (MNRAS)
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The 39m E-ELT (ESO)The 39m E-ELT (ESO)
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E-ELT and CODEX in 1 slideE-ELT and CODEX in 1 slide
Gilmozzi & Spyromilio, The Messenger 127, 11 (2007)
J. Liske et al., 0802.1532 (MNRAS)
European Extremely Large telescope (E-ELT):European Extremely Large telescope (E-ELT): Estimated completion: 2020-22Estimated completion: 2020-22 Aperture (diameter): Aperture (diameter): 39.3m39.3m Type: optical to mid-infraredType: optical to mid-infrared Cost: ~1 B€ (including 1Cost: ~1 B€ (including 1stst generation instruments) generation instruments) BrazilBrazil is joining ESO... (...) is joining ESO... (...)
Cosmic Dynamics Experiment (CODEX):Cosmic Dynamics Experiment (CODEX): High resolution super-stable spectrograph in E-ELTHigh resolution super-stable spectrograph in E-ELT Precursor in VLT (~2014): ESPRESSOPrecursor in VLT (~2014): ESPRESSO (Echelle SPectrograph for (Echelle SPectrograph for
Rocky Exoplanet- and Stable Spectroscopic Observations)Rocky Exoplanet- and Stable Spectroscopic Observations)
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Redshift Drift in Dark Energy modelsRedshift Drift in Dark Energy models
Balbi & Quercellini, 0704.2350 (MNRAS)
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Redshift Drift in Redshift Drift in LTBLTB
The Sandage Effect The Sandage Effect (or redshift drift) in (or redshift drift) in LTB is LTB is very very differentdifferent from from ΛΛCDM!CDM!
10 years
5 years
15 yearsQuartin & Amendola 0909.4954 (PRD)
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Gaia in 1 slideGaia in 1 slide
Cost: ~ 700Cost: ~ 700M€ M€
Broad scientific goalsBroad scientific goals
Allows us to Allows us to detectdetect large-scale deviations from isotropy large-scale deviations from isotropy through observations ofthrough observations of proper motions of quasars proper motions of quasars
GaiaGaia for cosmologists: for cosmologists: astrometry measurements with an astrometry measurements with an
accuracy of about accuracy of about 10 – 200 10 – 200 μμasas astrometric measurements of some astrometric measurements of some
500,000+500,000+ distant quasars distant quasarsLaunch: 2013
Quercellini, Quartin & Amendola 0809.3675 (PRL)
Quercellini, Cabella, Amendola, Quartin & Balbi 0905.4853 (PRD)
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The Cosmic Parallax effectThe Cosmic Parallax effect
In a FRW metric, In a FRW metric, ΔΔttγγ ≡≡ γγ22 – – γγ11 = 0. = 0.
In any anisotropic metric, however, ΔIn any anisotropic metric, however, Δttγ γ ≠≠ 0, and we have 0, and we have cosmic parallax.cosmic parallax.
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SNe off→SNe off→ -center dist. d-center dist. dobsobs ≤≤ 15%15% of void radius (~250 Mpc) of void radius (~250 Mpc)
CMB dipole off-ce. dist. d→CMB dipole off-ce. dist. d→ obsobs ≤≤ 2%2% of void rad. (~30 Mpc) of void rad. (~30 Mpc)
Cosmic Parallax with GaiaCosmic Parallax with Gaia
Off-center distance constrains (Mpc)Off-center distance constrains (Mpc)
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Cosmic Parallax in other modelsCosmic Parallax in other models
The cosmic parallax effect is sensitive to “any kind” of The cosmic parallax effect is sensitive to “any kind” of anisotropy anisotropy (technically, to the (technically, to the shearshear);); Measurement of Measurement of late-time anisotropylate-time anisotropy!! Different anisotropic models Different anisotropic models → → different different multipole multipole
dependencedependence;; Primordial anisotropy gets diluted with expansionPrimordial anisotropy gets diluted with expansion
Present anisotropy →Present anisotropy → anisotropic pressure fieldanisotropic pressure field!!
Important Important consistency checkconsistency check of our assumptions. of our assumptions.
Koivisto & MotaarXiv:0707.0279 (ApJ)arXiv:0801.3676 (JCAP)
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Cosmic Parallax in Bianchi ICosmic Parallax in Bianchi I~ 0.2 μas / year
Quercellini, Cabella, Amendola, Quartin & Balbi 0905.4853 (PRD)
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ConclusionsConclusions
Supernova can constrain also perturbation parameters!Supernova can constrain also perturbation parameters! Measure Measure σσ88 to ~1% level with LSST. to ~1% level with LSST.
Inhomogeneity & Anisotropy must be better constrainedInhomogeneity & Anisotropy must be better constrained We want cosmology with both We want cosmology with both precisionprecision & & accuracyaccuracy
Redshift drift – Redshift drift – inhomogeneityinhomogeneity probe probe Rule out void models @Rule out void models @ 5σ5σ with 10 years of E-ELT with 10 years of E-ELT
Cosmic parallax – Cosmic parallax – anisotropyanisotropy probe probe notnot a regular parallax! a regular parallax! Can be constrained with GaiaCan be constrained with Gaia
Obrigado!