EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGESCALE STRUCTURE
Abstract
We show how the nonlinearity of general relativity generates a characteristic nonGaussian signal in cosmological largescale structure that we calculate at all perturbative orders in a largescale limit. Newtonian gravity and general relativity provide complementary theoretical frameworks for modeling largescale structure in ΛCDM cosmology; a relativistic approach is essential to determine initial conditions, which can then be used in Newtonian simulations studying the nonlinear evolution of the matter density. Most inflationary models in the very early universe predict an almost Gaussian distribution for the primordial metric perturbation, ζ. However, we argue that it is the Ricci curvature of comovingorthogonal spatial hypersurfaces, R, that drives structure formation at large scales. We show how the nonlinear relation between the spatial curvature, R, and the metric perturbation, ζ, translates into a specific nonGaussian contribution to the initial comoving matter density that we calculate for the simple case of an initially Gaussian ζ. Our analysis shows the nonlinear signature of Einstein's gravity in largescale structure.
 Authors:
 Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth PO1 3FX (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22364938
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal Letters; Journal Volume: 794; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPUTERIZED SIMULATION; COSMOLOGY; DENSITY; DISTURBANCES; GAUSS FUNCTION; GENERAL RELATIVITY THEORY; GRAVITATION; METRICS; NONLINEAR PROBLEMS; NONLUMINOUS MATTER; RELATIVISTIC RANGE; UNIVERSE
Citation Formats
Bruni, Marco, Hidalgo, Juan Carlos, and Wands, David, Email: hidalgo@fis.unam.mx. EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGESCALE STRUCTURE. United States: N. p., 2014.
Web. doi:10.1088/20418205/794/1/L11.
Bruni, Marco, Hidalgo, Juan Carlos, & Wands, David, Email: hidalgo@fis.unam.mx. EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGESCALE STRUCTURE. United States. doi:10.1088/20418205/794/1/L11.
Bruni, Marco, Hidalgo, Juan Carlos, and Wands, David, Email: hidalgo@fis.unam.mx. 2014.
"EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGESCALE STRUCTURE". United States.
doi:10.1088/20418205/794/1/L11.
@article{osti_22364938,
title = {EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGESCALE STRUCTURE},
author = {Bruni, Marco and Hidalgo, Juan Carlos and Wands, David, Email: hidalgo@fis.unam.mx},
abstractNote = {We show how the nonlinearity of general relativity generates a characteristic nonGaussian signal in cosmological largescale structure that we calculate at all perturbative orders in a largescale limit. Newtonian gravity and general relativity provide complementary theoretical frameworks for modeling largescale structure in ΛCDM cosmology; a relativistic approach is essential to determine initial conditions, which can then be used in Newtonian simulations studying the nonlinear evolution of the matter density. Most inflationary models in the very early universe predict an almost Gaussian distribution for the primordial metric perturbation, ζ. However, we argue that it is the Ricci curvature of comovingorthogonal spatial hypersurfaces, R, that drives structure formation at large scales. We show how the nonlinear relation between the spatial curvature, R, and the metric perturbation, ζ, translates into a specific nonGaussian contribution to the initial comoving matter density that we calculate for the simple case of an initially Gaussian ζ. Our analysis shows the nonlinear signature of Einstein's gravity in largescale structure.},
doi = {10.1088/20418205/794/1/L11},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 794,
place = {United States},
year = 2014,
month =
}

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