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arXiv · 0807.0401

Description of our cosmological spacetime as a perturbed conformal Newtonian metric and implications for the backreaction proposal for the accelerating universe

Edward W. Kolb·Valerio Marra·Sabino Matarrese
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Abstract

It has been argued that the spacetime of our universe can be accurately described by a perturbed conformal Newtonian metric, and hence even large density inhomogeneities in a dust universe can not change the observables predicted by the homogeneous dust model. In this paper we study a spherically symmetric dust model and illustrate conditions under which large spatial variations in the expansion rate can invalidate the argument.

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Edward W. Kolb, Valerio Marra, Sabino Matarrese. 2008-11-05. Description of our cosmological spacetime as a perturbed conformal Newtonian metric and implications for the backreaction proposal for the accelerating universe. https://doi.org/10.1103/physrevd.78.103002

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