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arXiv · 1203.4790

A simplified structure for the second order cosmological perturbation equations

Claes Uggla·John Wainwright
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Abstract

Increasingly accurate observations of the cosmic microwave background and the large scale distribution of galaxies necessitate the study of nonlinear perturbations of Friedmann-Lemaitre cosmologies, whose equations are notoriously complicated. In this paper we present a new derivation of the governing equations for second order perturbations within the framework of the metric-based approach that is minimal, as regards amount of calculation and length of expressions, and flexible, as regards choice of gauge and stress-energy tensor. Because of their generality and the simplicity of their structure our equations provide a convenient starting point for determining the behaviour of nonlinear perturbations of FL cosmologies with any given stress-energy content, using either the Poisson gauge or the uniform curvature gauge.

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Claes Uggla, John Wainwright. 2012-03-21. A simplified structure for the second order cosmological perturbation equations. https://doi.org/10.1007/s10714-012-1492-7

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