表紙 T=2.725K Cosmic Microwave Background CMB Scale factor Curvature Hubble parameter Density parameter cosmological constant (dark energy) Standard Inflation predicts 1 with high accuracy. 一様等方宇宙 cluster 1022m 階層 1020m 1012m Solar system galaxy 107m 1024m supercluster 1m Earth grew out of linear perturbations under the gravity Linear perturbation b g b g ds 1 2 ( x , t ) dt a (t ) 1 2 ( x , t ) dx 2 2 2 Potential fluctuation Power Spectrum of Initial Fluctuation P( k , ti ) | k (ti )|2 A H Cosmological Parameters H, , ,... 2 Curvature fluctuation Large-Scale Structures Present Power Spectrum P( k , t0 ) | k (t0 )|2 Anisotropies in cosmic microwave background Angular Power Spectrum Cl T T 10 5 COBE COsmic Background Explorer 1993 WMAP Wilkinson Microwave Anisotropy Probe 2003 2001/6/30 2001/7/30 2002/4: first full-sky map 2002/10: second map 2001/10/1 size 5m、weight 840kg COBEのbeam widthは7度だった。 Full Sky Map of Cosmic Microwave Background Radiation -200 T(μK) +200 Temperature fluctuation is Gaussian distributed. Power spectrum determines the statistical distribution. Three dimensional spatial quantities: Fourier expansion 3 ikx d k ( x , t ) k (t )e Length scale r: r 2 k z bg 3 2 b g k (t ) k * (t ) P( k , t ) 3 k k Power Spectrum: c hz d 3k b g Correlation Function: ( x , t ) ( y, t ) x y P( k , t )e 3 ik x y b2 g Two dimensional angular quantities: Spherical harmonics expansion T T bg l bg , almYlm , l 0 m l Angular scaleθ: al1m1 al*2m2 Cl1 l1l2 m1m2 Angular Power Spectrum: Cl bg Angular Correlation Function: C 12 T T 1 2 2 12 l l 0 b , g b , g 1 2l 1 , g b , g Cb g C Pb cos g b T T 4 1 l l 12 12 1 2 2 ( 1)C 2 So many data points! m0 Luminosity density and average M/L of galaxies m0 0.2 0.5 Cluster baryon fraction from X-ray emissivity and baryon density from primordial nucleosynthesis m0 0.35 0.07 Shape parameter of the transfer function of CDM scenario of structure formation m0h 0.15 0.3 m0 Many others 0.35 m0 0.3 0 dL q0 Type Ia Supernovae m-z relation Fz 1 q z IJ, H G H 2 K a 1 b 2 g aH 2 1 0 0 2 M 2 log(dL) t0 z 0 1.25m0 0.5 0.5 SNIa+CMB +Matter density 0 K 0 0 m0 H0 HST Key Project Cepheids H0 =75±10km/s/Mpc SNIa H0 =71±2(stat)±6(syst)km/s/Mpc Tully-Fisher H0 =71±3±7km/s/Mpc Surface Brightness Fluctuation H0 =70±5±6km/s/Mpc SNII H0 =72±9±7km/s/Mpc Fundamental Plane of Elliptical Galaxies H0 =82±6±9km/s/Mpc Summary H0 =72±8km/s/Mpc (Freedman et al ApJ 553(2001)47) m0 0.3 0 0.7 m0 0 1, K 0 Concordance Model as predicted by Inflation Cosmic age t0 (0.9 1.0) H 1 0 1 0 H0 =72±8km/s/Mpc, H 12.2 13.6 16.9Gyr t0 11 17Gyr centered around t0 13Gyr Observation: t0 11 14Gyr from globular cluster t0 12 15Gyr from cosmological nuclear chronology Concordance Model was confirmed with high accuracy. (with the help of the HST value of Hubble parameter.) 6 Parameters Normalization of Fluctuations Spectral index Baryon density Dark matter density Cosmological Constant Hubble parameter in Spatially Flat Universe 899 data points are fit. Approximately scale-invariant spectrum, which is predicted by standard inflation models, fits the data. But we may also find several interesting features beyond a simple power-law spectrum… 表紙 c h b g The Boltzmann equation for photon distribution f p , x in a perturbed spacetime ds2 1 2 ( x, t ) dt 2 a 2 (t ) 1 2 ( x, t ) dx 2 Df f dx f dp C f Collision term due to Dt x dt p dt the Thomson scattering b g 8 2 C f xe ne T , T 3me2 free electron density We consider temperature fluctuation averaged over photon energy in Fourier and multipole spaces. T i T k :conformal time , , k , , k , , k , c T hTb g b g k direction vector of photon d k 2 1 C ( , k , ) (i) ( , k ) P ( ), 0 (2 )3 4 0 3 (0 , k ) 2 1 2 . directionally averaged Boltzmann equation L M N b g ik 0 1 2 P2 ( ) iVb 10 collision term axe ne T conformal time O P Q Baryon (electron) velocity Euler equation for baryons b 3 b a Vb Vb k V Vb , R a R pb p 4 d i Metric perturbation generated during inflation k2 k2 3H 2 , 2 :Poisson equation 2 a a 2 Boltzmann eq. can be transformed to an integral equation. b gb, , k g zm iV ()e 0 0 0 0 b ( ) b g re e ( ) b gd ik 0 b gb, , k g zm iV ()e 0 0 0 () 0 b z 0 ( ) ( )d b z 0 g re e ( ) b gd ik 0 axe ne T d Optical depth If we treat the decoupling to occur instantaneously at b g e ( ) d Visibility function e ( ) 1 no scattering many scattering b g v () ()e ( ) d d , d 0 now b g b gb gb g , 0 , k 0 , k 0 iVb d e b g ik d 0 Last scattering surface b e b g z 0 ik 0 d Propagation gd In reality, decoupling requires finite time and the LSS has a finite thickness. Short-wave fluctuations that oscillate many times during it 2 damped by a factor e bk k D gwith k D 10h1Mpc corresponding to 0.1deg. Observable quantity F 1 b , , k g G H4 0 0 Ib g JK 2 1 ik b d 0 g b k kD g iVb d e e 3 on Last scattering surface Integrated SachsWolfe effect b e b g z 0 d 1 d : Temperature fluctuations 4 ik 0 gd small scale b g:Doppler effect iVb d b g:Gravitational Redshift Sachs-Wolfe effect 1 d 3 Large scale They can be calculated from the Boltzman/Euler/Poisson eqs., if the initial condition of k,ti and cosmological parameters are given. b gd e b gb g g z We need to calculate b and V b at the Last scattering surface g g b g b gb b kk g b g , 0 , k 0 , k 0 iVb d e e ik d 0 0 d b 2 D 0 ik 0 d d when photons and baryons are decoupled. Behavior of photon-baryon fluid in the tight coupling regime Small scales: cs H 1 a k below sound horizon (Jeans scale) 3 3Rgis the sound speed.) Oscillatory ( cs2 1 b Large scales: k 0 0 const Specifically they are given by the solution of the following eqn. 2 R a R a k 0 0 k 2 cs2 0 F () 1 R a 1 R a 3 source term is given by metric perturbation. Initial condition of 0 is also given by k generated during inflation (if adiabatic fluc.) Inflation 図のような幾何学的関係からフーリエ空間の量がmultipole 空間 の角度パワースペクトル C に関係づけられる。 Fourier modes are related with angular multipoles as depicted in the figure. r ~2π/k LSS d Θ~π/l b b g g , 0 , k ( i ) l l 0 , k Pl ( ) l l~kdにピーク Observer b g Cl d k l 0 , k 4 (2 ) 3 (2l 1) 2 z 3 2 Sound horizon at LSS corresponds to about 1 degree, which explains the location of the peak 180 200 小スケールで振動 Gravitational 重一 力般 赤相 方対 偏論 移的 流体力学的揺らぎ 大スケールで ほぼ一定 hydorodynamical The shape of the angular power spectrum depends on P(k , ti ) | k (ti ) |2 Ak ns 4 (spectral index ns etc)as well as the values of cosmological parameters. ( ns 1 corresponds to the scaleinvariant primordial fluctuasion.) Increasing baryon density relatively lowers radiation pressure, which results in higher peak. Decreasing Ω(open Universe)makes opening angle smaller so that the multipole l at the peak is shifted to a larger value. Smaller Hubble parameter means more distant LSS with enhanced early ISW effect. Λalso makes LSS more distant, shifting the peak toward right with enhanced Late ISW effect. Thick line 1, 0 n 1, h 0.5 1 0.5 0.3 0.05 0.03 0.01 b h2 0.01 Old standard CDM model. 0.7 0.3 0.5 0.7 0.3 0 表紙
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