Perturbations in generalized Galileon theories
High Energy Physics - Theory
2018-01-03 v2 General Relativity and Quantum Cosmology
Abstract
We discuss the approaches by Deffayet et al. (DPSV) and Kobayashi et al. (KYY) to the analysis of linearized scalar perturbations about a spatially flat FLRW background in Horndeski theory. We identify additional, potentially important terms in the DPSV approach. However, these terms vanish upon a judicious gauge choice. We derive a gauge invariant quadratic action for metric and Galileon perturbations in and theories and show that actions obtained in the DPSV and KYY approaches follow from this gauge invariant action in particular gauges.
Cite
@article{arxiv.1708.04262,
title = {Perturbations in generalized Galileon theories},
author = {R. Kolevatov and S. Mironov and V. Rubakov and N. Sukhov and V. Volkova},
journal= {arXiv preprint arXiv:1708.04262},
year = {2018}
}
Comments
This is a journal version of the article. The proof of the statement made in Section 3 has been considerably revised. The paper consists of 13 pages