English

Cosmic Inhomogeneities and the Average Cosmological Dynamics

Astrophysics 2008-11-26 v3 General Relativity and Quantum Cosmology High Energy Physics - Theory

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.

Keywords

Cite

@article{arxiv.0806.3497,
  title  = {Cosmic Inhomogeneities and the Average Cosmological Dynamics},
  author = {Aseem Paranjape and T. P. Singh},
  journal= {arXiv preprint arXiv:0806.3497},
  year   = {2008}
}

Comments

5 pages, 2 figures, revtex4; v3 -- Text shortened to match published version. Some typos fixed. No physics changes

R2 v1 2026-06-21T10:53:03.635Z