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Title: Conservation of nonlinear curvature perturbations on super-Hubble scales

Abstract

We consider general, non-linear curvature perturbations on scales greater than the Hubble horizon scale by invoking an expansion in spatial gradients, the so-called gradient expansion. After reviewing the basic properties of the gradient expansion, we derive the conservation law for non-linear curvature perturbations for an isentropic fluid. We also define the gauge-invariant curvature perturbation under a finite shift of time-slicing, and derive the non-linear genralization of the {delta}N formalism. The results obtained are straight-forward generalisations of those already proven in linear perturbation theory, and the equations are simple, resembling closely the first-order equations.

Authors:
 [1]
  1. Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
Publication Date:
OSTI Identifier:
20729223
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 805; Journal Issue: 1; Conference: PASCOS 2005: 11. international symposium on particles, strings, and cosmology, Gyeongju (Korea, Republic of), 30 May - 4 Jun 2005; Other Information: DOI: 10.1063/1.2149682; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CONSERVATION LAWS; COSMOLOGY; DISTURBANCES; EXPANSION; FIELD EQUATIONS; GAUGE INVARIANCE; NONLINEAR PROBLEMS; PERTURBATION THEORY; QUANTUM FIELD THEORY

Citation Formats

Sasaki, Misao. Conservation of nonlinear curvature perturbations on super-Hubble scales. United States: N. p., 2005. Web. doi:10.1063/1.2149682.
Sasaki, Misao. Conservation of nonlinear curvature perturbations on super-Hubble scales. United States. doi:10.1063/1.2149682.
Sasaki, Misao. Fri . "Conservation of nonlinear curvature perturbations on super-Hubble scales". United States. doi:10.1063/1.2149682.
@article{osti_20729223,
title = {Conservation of nonlinear curvature perturbations on super-Hubble scales},
author = {Sasaki, Misao},
abstractNote = {We consider general, non-linear curvature perturbations on scales greater than the Hubble horizon scale by invoking an expansion in spatial gradients, the so-called gradient expansion. After reviewing the basic properties of the gradient expansion, we derive the conservation law for non-linear curvature perturbations for an isentropic fluid. We also define the gauge-invariant curvature perturbation under a finite shift of time-slicing, and derive the non-linear genralization of the {delta}N formalism. The results obtained are straight-forward generalisations of those already proven in linear perturbation theory, and the equations are simple, resembling closely the first-order equations.},
doi = {10.1063/1.2149682},
journal = {AIP Conference Proceedings},
number = 1,
volume = 805,
place = {United States},
year = {Fri Dec 02 00:00:00 EST 2005},
month = {Fri Dec 02 00:00:00 EST 2005}
}
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