Backreaction as an alternative to dark energy and modified gravity
Cosmology and Nongalactic Astrophysics
2015-03-17 v1 General Relativity and Quantum Cosmology
Abstract
The predictions of homogeneous and isotropic cosmological models with ordinary matter and gravity are off by a factor of two in the late universe. One possible explanation is the known breakdown of homogeneity and isotropy due to the formation of non-linear structures. We review how inhomogeneities affect the average expansion rate and can lead to acceleration, and consider a semi-realistic model where the observed timescale of ten billion years emerges from structure formation. We also discuss the relation between the average expansion rate and observed quantities.
Cite
@article{arxiv.1012.0784,
title = {Backreaction as an alternative to dark energy and modified gravity},
author = {Syksy Rasanen},
journal= {arXiv preprint arXiv:1012.0784},
year = {2015}
}
Comments
22 pages, 4 figures. Contribution to the proceedings of the "Beyond the Concordance Model" workshop held at The Stellenbosch Institute for Advanced Study, 23.-27. August 2010