A relativistic signature in large-scale structure

Abstract

In General Relativity, the constraint equation relating metric and density perturbations is inherently nonlinear, leading to an effective non-Gaussianity in the dark matter density field on large scales - even if the primordial metric perturbation is Gaussian. Intrinsic non-Gaussianity in the large-scale dark matter overdensity in GR is real and physical. However, the variance smoothed on a local physical scale is not correlated with the large-scale curvature perturbation, so that there is no relativistic signature in the galaxy bias when using the simplest model of bias. It is an open question whether the observable mass proxies such as luminosity or weak lensing correspond directly to the physical mass in the simple halo bias model. If not, there may be observables that encode this relativistic signature.

8 pages, 2 figures. The original claim on galaxy bias for simple inflation models has been corrected; intrinsic non-Gaussianity in the matter density from GR effects is real, but observables that encode this remain to be found. Version accepted by Physics of the Dark Universe, Volume 13, September 2016, Pages 30-34

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Cited by in corpus (24)

• Large-Scale Galaxy Bias
• Galaxy bispectrum, primordial non-Gaussianity and redshift space distortions
• How Gaussian can our Universe be?
• The Hunt for Primordial Interactions in the Large Scale Structures of the Universe
• Cancellation of quantum corrections on the soft curvature perturbations
• Relativistic wide-angle galaxy bispectrum on the light-cone
• Squeezed Bispectrum in the $\delta N$ Formalism: Local Observer Effect in Field Space
• Galaxy Power Spectrum in General Relativity
• The observed galaxy bispectrum from single-field inflation in the squeezed limit
• Imprints of local lightcone projection effects on the galaxy bispectrum. II
• Imprints of local lightcone projection effects on the galaxy bispectrum. III Relativistic corrections from nonlinear dynamical evolution on large-scales
• Local primordial non-Gaussianity in the relativistic galaxy bispectrum
• General relativistic effects in the galaxy bias at second order
• General Relativistic Cosmological N-body Simulations I: time integration
• Measuring the Energy Scale of Inflation with Large Scale Structures
• How Gaussian can the Sky be? Primordial Non-Gaussianity from Quantum Information
• The galaxy bias at second order in general relativity with Non-Gaussian initial conditions
• fNL - gNL mixing in the matter density field at higher orders
• Large-scale imprint of relativistic effects in the cosmic magnification
• Gravitational Redshifts in Clusters and Voids
• Relativistic second-order initial conditions for simulations of large-scale structure
• Relativistic and non-Gaussianity contributions to the one-loop power spectrum
• Breaking the Single Clock Symmetry: measuring single-field inflation non-Gaussian features
• Gravitational redshift in the void-galaxy cross-correlation function in redshift space