Averaging and Cosmological Observations

Abstract

The gravitational field equations on cosmological scales are obtained by averaging the Einstein field equations of general relativity. By assuming spatial homogeneity and isotropy on the largest scales, the local inhomogeneities affect the dynamics though correction (backreaction) terms, which can lead to behaviour qualitatively and quantitatively different from the Friedmann-Lemaître-Robertson-Walker models. The effects of averaging on cosmological observations are discussed. It is argued that, based on estimates from observational data, the backreaction (and, in particular, the averaged spatial curvature) can have a very significant dynamical effect on the evolution of the Universe and must be taken into account in observational cosmology.

9 pages

Cited by in corpus (8)

• Relativistic cosmology and large-scale structure
• Quasi-local variables in spherical symmetry: numerical applications to dark matter and dark energy sources
• Averaging Robertson-Walker Cosmologies
• A Complete Cosmological Solution to the Averaged Einstein Field Equations as found in Macroscopic Gravity
• Quasi-local variables, non-linear perturbations and back-reaction in spherically symmetric spacetimes
• Null geodesics and observational cosmology
• Cosmological Observations: Averaging on the Null Cone
• Averaging in cosmological models