arXiv 0807.04012008-07astro-phgr-qc

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

备注：: 22 pages, 8 figures; replaced to fit the version accepted for publication in Phys. Rev. D
发表信息：: Phys.Rev.D78:103002,2008
DOI：: 10.1103/PhysRevD.78.103002

英文摘要：

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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