Relativistic galaxy number counts to second order and their bispectrum.
@inproceedings{Dio2014RelativisticGN, title={Relativistic galaxy number counts to second order and their bispectrum.}, author={Enea di Dio and Ruth Durrer and G. Marozzi and Francesco Montanari}, year={2014} }
We determine the number counts to second order in cosmological perturbation theory in the Poisson gauge and allowing for anisotropic stress. The calculation is performed using an innovative approach based on the recently proposed "geodesic light-cone" gauge. This allows us to determine the number counts in a purely geometric way, without using Einstein's equation. The result is valid for general dark energy models and (most) modified gravity models. We then evaluate numerically the relevant…
57 Citations
The relativistic galaxy number counts in the weak field approximation
- Physics
- 2020
We present a novel approach to compute systematically the relativistic projection effects at any order in perturbation theory within the weak field approximation. In this derivation the galaxy number…
Galaxy number counts at second order: an independent approach
- PhysicsClassical and Quantum Gravity
- 2021
Next generation surveys will be capable of determining cosmological parameters beyond percent level. To match this precision, theoretical descriptions should look beyond the linear perturbations to…
The observed galaxy bispectrum from single-field inflation in the squeezed limit
- PhysicsJournal of Cosmology and Astroparticle Physics
- 2018
Using the consistency relation in Fourier space, we derive the observed galaxy bispectrum from single-field inflation in the squeezed limit, in which one of the three modes has a wavelength much…
Cosmological simulations of number counts
- PhysicsJournal of Cosmology and Astroparticle Physics
- 2021
In this paper we present for the first time the angular power spectra C ℓ(z,z') for number counts from relativistic N-body simulations. We use the relativistic N-body code gevolution with its exact…
Relativistic wide-angle galaxy bispectrum on the light-cone
- Physics
- 2018
Given the important role that the galaxy bispectrum has recently acquired in cosmology and the scale and precision of forthcoming galaxy clustering observations, it is timely to derive the full…
From matter to galaxies: general relativistic bias for the one-loop bispectrum
- Physics
- 2019
We write down the Lagrangian bias expansion in general relativity up to 4th order in terms of operators describing the curvature of an early-time hypersurface for comoving observers. They can be…
Covariant decomposition of the non-linear galaxy number counts and their monopole
- PhysicsJournal of Cosmology and Astroparticle Physics
- 2021
We present a fully non-linear and relativistically covariant expression for the observed galaxy density contrast. Building on a null tetrad tailored to the cosmological observer's past light cone, we…
A Consistency Relation for the Observed Galaxy Bispectrum and the Local non-Gaussianity from Relativistic Corrections
- Physics
- 2015
We obtain a consistency relation for the observed three-point correlator of galaxies. It includes relativistic effects and it is valid in the squeezed limit. Furthermore, the consistency relation is…
A general relativistic signature in the galaxy bispectrum
- Physics
- 2016
Next-generation galaxy surveys will increasingly rely on the galaxy bispectrum to improve cosmological constraints, especially on primordial non-Gaussianity. A key theoretical requirement that…
Vector perturbations of galaxy number counts
- Physics
- 2016
We derive the contribution to relativistic galaxy number count fluctuations from vector and tensor perturbations within linear perturbation theory. Our result is consistent with the the relativistic…
References
SHOWING 1-10 OF 56 REFERENCES
Observed galaxy number counts on the lightcone up to second order: II. Derivation
- Physics
- 2014
We present a detailed derivation of the observed galaxy number over-density on cosmological scales up to second order in perturbation theory. We include all relativistic effects that arise from…
Observed galaxy number counts on the lightcone up to second order: I. Main result
- Physics
- 2014
We present the galaxy number overdensity up to second order in redshift space on cosmological scales for a concordance model. The result contains all general relativistic effects up to second order…
Beyond the Linear-Order Relativistic Effect in Galaxy Clustering: Second-Order Gauge-Invariant Formalism
- Physics
- 2014
We present the second-order general relativistic description of the observed galaxy number density in a cosmological framework. The observed galaxy number density is affected by the volume and the…
Cosmic shear bispectrum from second-order perturbations in general relativity
- Physics
- 2012
Future lensing surveys will be nearly full-sky and reach an unprecedented depth, probing scales closer and closer to the Hubble radius. This motivates the study of the cosmic shear beyond the…
The luminosity distance–redshift relation up to second order in the Poisson gauge with anisotropic stress
- Physics
- 2015
We present the generalization of previously published results, about the perturbed redshift and the luminosity–redshift relation up to second order in perturbation theory, for the case of the Poisson…
The second-order luminosity-redshift relation in a generic inhomogeneous cosmology
- Physics
- 2012
After recalling a general non-perturbative expression for the luminosity-redshift relation holding in a recently proposed ``geodesic light-cone" gauge, we show how it can be transformed to…
Value of H(0) in the inhomogeneous universe.
- PhysicsPhysical review letters
- 2014
It is argued that cosmic variance (i.e., the effects of the local structure) is of the same order of magnitude as the current observational errors and must be taken into account in local measurements of the Hubble expansion rate.
The cosmological background of vector modes
- Physics
- 2008
We investigate the spectrum of vector modes today which is generated at second order by density perturbations. The vector mode background that is generated by structure formation is small but in…
Light-cone averaging in cosmology: formalism and applications
- Physics
- 2011
We present a general gauge invariant formalism for defining cosmological averages that are relevant for observations based on light-like signals. Such averages involve either null hypersurfaces…