General cosmological perturbations in teleparallel gravity
Abstract
We discuss linear perturbations of the most general class of teleparallel spacetimes with cosmological symmetry, and perform a decomposition of these perturbations into irreducible components. We then study their behavior under gauge transformations, i.e., infinitesimal diffeomorphisms of the background spacetime, and derive a full set of gauge-invariant perturbation variables. Comparing our results with perturbations around the diagonal tetrad corresponding to a spatially flat teleparallel background cosmology, we see the appearance of new terms which depend on the particular choice of a cosmologically symmetric background tetrad. Finally, we demonstrate the application of our findings to teleparallel gravity theories. For convenience, results are displayed both in general and conformal coordinates.
Cite
@article{arxiv.2011.02491,
title = {General cosmological perturbations in teleparallel gravity},
author = {Manuel Hohmann},
journal= {arXiv preprint arXiv:2011.02491},
year = {2021}
}
Comments
18 pages, no figures; invited contribution to the Eur. Phys. J. Plus focus point "Modified Gravity Theories and Cosmology"; updated references to accepted version