Scale dependence of cosmological backreaction
Abstract
Because of the noncommutation of spatial averaging and temporal evolution, inhomogeneities and anisotropies (cosmic structures) influence the evolution of the averaged Universe via the cosmological backreaction mechanism. We study the backreaction effect as a function of averaging scale in a perturbative approach up to higher orders. We calculate the hierarchy of the critical scales, at which 10% effects show up from averaging at different orders. The dominant contribution comes from the averaged spatial curvature, observable up to scales of ∼200Mpc. The cosmic variance of the local Hubble rate is 10% (5%) for spherical regions of radius 40 (60) Mpc. We compare our result to the one from Newtonian cosmology and Hubble Space Telescope Key Project data.
 Publication:

Physical Review D
 Pub Date:
 October 2008
 DOI:
 10.1103/PhysRevD.78.083531
 arXiv:
 arXiv:0710.5073
 Bibcode:
 2008PhRvD..78h3531L
 Keywords:

 98.65.Dx;
 95.36.+x;
 98.80.Es;
 98.80.Jk;
 Superclusters;
 largescale structure of the Universe;
 Dark energy;
 Observational cosmology;
 Mathematical and relativistic aspects of cosmology;
 Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 6 pages, 2 figures