The cosmological backreaction: gauge (in)dependence, observers and scalars
Abstract
We discuss several issues related to a recent proposal for defining classical spatial averages to be used in the so-called cosmological backreaction problem. In the large averaging-volume limit all gauge dependence disappears and different averages can be univocally characterized by the observers associated with different scalar fields. The relation between such averaging procedure and the standard one is emphasized and a gauge invariant way to select different observers is presented. For finite averaging volumes we show that, within our proposal, a residual gauge dependence is left, but is suppressed by several effects.
Keywords
Cite
@article{arxiv.1011.4921,
title = {The cosmological backreaction: gauge (in)dependence, observers and scalars},
author = {Giovanni Marozzi},
journal= {arXiv preprint arXiv:1011.4921},
year = {2011}
}
Comments
16 pages, no figures. Comments and references added, errors and typos corrected, conclusions unchanged. Comment added and typos corrected, version published in JCAP