Constraints on backreaction in dust universes

  title={Constraints on backreaction in dust universes},
  author={Syksy Rasanen},
  journal={Classical and Quantum Gravity},
  • S. Rasanen
  • Published 1 April 2005
  • Physics
  • Classical and Quantum Gravity
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… 
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