# Constraints on backreaction in dust universes

@article{Rasanen2006ConstraintsOB, title={Constraints on backreaction in dust universes}, author={Syksy Rasanen}, journal={Classical and Quantum Gravity}, year={2006}, volume={23}, pages={1823-1835} }

We study backreaction in dust universes using exact equations which do not rely on perturbation theory, concentrating on theoretical and observational constraints. In particular, we discuss the recent suggestion (Kolb et al 2005 Preprint hep-th/0503117) that superhorizon perturbations could explain present-day accelerated expansion as a useful example which can be ruled out. We note that a backreaction explanation of late-time acceleration will have to involve spatial curvature and subhorizon…

## 74 Citations

Constraints on backreaction in dust universes RASANEN

- Physics
- 2017

We study backreaction in dust universes using exact equations which do not rely on perturbation theory, concentrating on theoretical and observational constraints. In particular, we discuss the…

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- 2011

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- 2005

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- Physics
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We discuss the Buchert equations, which describe the average expansion of an inhomogeneous dust universe. In the limit of small perturbations, they reduce to the Friedmann–Robertson–Walker equations.…

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- 2013

We propose a backreaction toy model with realistic features and confront it with the Union2.1 supernova data. The model provides a good fit even though the expansion history is quite different from…

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- Physics
- 2008

The problem of corrections to Einstein's equations arising from averaging of inhomogeneities (backreaction) in the cosmological context has gained considerable attention recently. We present results…

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