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arXiv · 0806.3497

Cosmic Inhomogeneities and the Average Cosmological Dynamics

Aseem Paranjape·T. P. Singh
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Abstract

If general relativity (GR) describes the expansion of the Universe, the observed cosmic acceleration implies the existence of a `dark energy'. However, while the Universe is on average homogeneous on large scales, it is inhomogeneous on smaller scales. While GR governs the dynamics of the \emph{in}homogeneous Universe, the averaged \emph{homogeneous} Universe obeys modified Einstein equations. Can such modifications alone explain the acceleration? For a simple generic model with realistic initial conditions, we show the answer to be `no'. Averaging effects negligibly influence the cosmological dynamics.

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Aseem Paranjape, T. P. Singh. 2008-11-01. Cosmic Inhomogeneities and the Average Cosmological Dynamics. https://doi.org/10.1103/physrevlett.101.181101

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