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Published byJanice Heath Modified over 9 years ago
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Acceleration of Universe Background level Evolution of expansion: H(a), w(a) degeneracy: DE & MG Perturbation level Evolution of inhomogeneity: G(a), G(a, k), Phi, Psi… Smoothing energy component or modified gravity? Scalar field F(R), DGP, TeVeS,
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Growth of LSS Expansion: H(a) consistency relation: H_growth vs. H_expansion Metric perturbation:
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Modified Gravity H(a) Modified Poisson equation. G_eff Parametrization Growth index (scale-independent)
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convergence power (cross) spectrum rich information (power spectrum, cross-spectrum) photo-z error
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standard ruler Spectroscopic survey δ field Growth factor G(z) v field (redshift distortion) β~ dlnG/dlna
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2009 XuGuangqi-Galieo conference 7 A sensitive measure of gravity Guzzo et al. 2008 Acquaviva et al. 2008 Spectroscopic redshift surveys Measure beta from the anisotropy Measure galaxy bias Obtain f Current measurements
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Standard Candle variation of SN peak L (after the standardization) photo-z error (without spectrum) z-dependent peak L (e.g. SN evolution, extinction)
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mass of clusters are not measured directly (except for WL) complex baryon physics (hydrodynamics, galaxies formation) SZ flux decrement, X-ray temperature, gas mass mass selection function
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number distribution angular density
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BAO Spectroscopic survey Photometric survey
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Supernovae 200 SNIa/year/deg^2 available for z<1.2 (limit for ground experiment) SN1: 50 /y/deg^2 SN2: 100 /y/deg^2 photo-z error N_c: # of spectra for calibration Systematics (Nuisance parameters) : absolute magnitude quadratic offset
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Weak Lensing (same as Sun lei & Zhao Gongbo)
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Clusters Count
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Genus Gaussian fluctuation: 3D (δ) 2D (weak lensing, κ)
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Resistant against: Bias, redshift distortion, weak nonliearity. In GR Invariant amplitude. Standard ruler In MG Introduce new scale-dependence time-varying Complementary to growth rate of matter fluctuation. Sensitive to scale-dependent modification at sub-horizon scale.
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Fisher calculation:
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Testing the (generalized) Poisson Equation 2009 XuGuangqi-Galieo conference 19 = Gravitational lensing from peculiar velocity ? Galaxy redshifts to recover redshift information (2D ->3D)
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2009 XuGuangqi-Galieo conference 20 LCDM f(R) DGP MOND/TeVeS ZPJ et al. 2007 E G will be measured to 1% level accuracy within two decades Promising to detect one percent level deviation from general relativity+canonical dark energy model (if systematics can be controlled)!
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2009 XuGuangqi-Galieo conference 21 ZPJ et al. 2008 eta can be measured to 10% accuracy. Errors in eta is larger than errors in E_G Even so, eta can have stronger discriminating power, in some cases. η of DGP differs significantly from that of LCDM. (E G of DGP is very close to that of LCDM.) eta and E_G are complementary DGP with high Omega_m SKA forecast DGP MOND TeVeS dark energy with anisotropic stress One can further construct an estimator of Lensing: Φ-Ψ; Peculiar velocity: Ψ
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