SEP.20-21.2006.KIAS KIAS WORKSHOP 1

Dark Energy Effects on CMB & LSS

The 2nd KIAS Workshop on Cosmology and Structure Formation

Seokcheon ( 碩天 large sky) LeeInstitute of Physics,

Academia Sinica

SEP.20-21.2006.KIAS KIAS WORKSHOP 2

Outline

Observable Impact of DE BAO, CL, SN, WL (Im)Perfect Dark Energy Fluid Effects on CMB and Matter Power Spectrum Summary

SEP.20-21.2006.KIAS KIAS WORKSHOP 3

Observable Impact of DE

Modification of z–d relation

: Baryon Acoustic Oscillations (BAO, R.Kron),

SuperNova (SN, G-C Liu), [δD] Effects on growth of structures

: Galaxy CLustering counting (CL, Z.Zheng),

Weak Lensing (WL, Sejong Univ),

ISW effect (C.G.Park)

SEP.20-21.2006.KIAS KIAS WORKSHOP 4

Observations & Measurements

SEP.20-21.2006.KIAS KIAS WORKSHOP 5

H(z) & δ(z)

Evolution of Background From WMAP data we ca

n find zeq ~ 5000 Flat Universe is preferred

by WMAP. i.e. Ωk = 0

Density fluctuation on small scales (sub-horizon scale)

SEP.20-21.2006.KIAS KIAS WORKSHOP 6

r(z) and dV(z)

FRW metric

Volume element

Proper distance

Comoving coordinate

SEP.20-21.2006.KIAS KIAS WORKSHOP 7

Imperfect DE Fluid

Cosmological fluid Adiabatic and entropic

sound speed (J-C Hwang) Dark energy rest frame Anisotropic stress of DE

SEP.20-21.2006.KIAS KIAS WORKSHOP 8

Effects of σ on δ & θ

For large scale source term : -(1+ω)(c_s^2-ω)θ/k^2 ω = -0.8 Dominate metric source term and

derive δ to smaller values k = 1.3 · 10^{-4} Mpc^{-1} (c_s^2, c_vis^2) = (0,0), (0.6,0),

(0,0.6),(0.6,0.6) δ gets smaller when DE dominate

(solid lines) Θ increases (dashed lines) ISW id enhanced as c^2 increase

s

SEP.20-21.2006.KIAS KIAS WORKSHOP 9

ISW Effects

C_{vis}^2 : 1.0, 0.1, 0.01, 0.001, 0

MD : total density grows in order to Φ,Ψ = const.

SEP.20-21.2006.KIAS KIAS WORKSHOP 10

Matter Power Spectrum

C_{vis}^2 = 1.0 Solid line : w=-1.2,

c_s^2=1.0 Dash-dotted : w=-

0.8,c_s^2=0 Dashed : w=-1.2 c_s^2=0 Thick : w=-0.8,

c_s^2=1.0

SEP.20-21.2006.KIAS KIAS WORKSHOP 30

Summary

As c_{vis}^2 ↑, δ↓ , θ↑, H/k^2(1+ω)θ↑ As c_{vis}^2 ↑, ISW ↑ Effects on MPS occurs only at large scales CMB’s only sensitive to <ω> Correlation to others BAO, CL, D(g), WL… Bispectra (? Y. Suto) DARK ENERGY IS NOWHERE!