A not so short note on the Klein-Gordon equation at second order
Astrophysics
2010-10-27 v5
Abstract
We give the governing equations for multiple scalar fields in a flat Friedmann-Robertson-Walker (FRW) background spacetime on all scales, allowing for metric and field perturbations up to second order. We then derive the Klein-Gordon equation at second order in closed form in terms of gauge-invariant perturbations of the fields in the uniform curvature gauge. We also give a simplified form of the Klein-Gordon equation using the slow-roll approximation.
Cite
@article{arxiv.astro-ph/0610864,
title = {A not so short note on the Klein-Gordon equation at second order},
author = {Karim A. Malik},
journal= {arXiv preprint arXiv:astro-ph/0610864},
year = {2010}
}
Comments
12 pages, revtex; V2: minor changes, typos and errors corrected (list of corrections added to appendix), conclusions unchanged; V3: minor changes, corresponds to published version; V4: minor changes, errors corrected; V5: minor changes, errors corrected