Classical stability of a homogeneous, anisotropic inflating space-time
Abstract
We study the classical stability of an anisotropic space-time seeded by a spacelike, fixed norm, dynamical vector field in a vacuum-energy-dominated inflationary era. It serves as a model for breaking isotropy during the inflationary era. We find that, for a range of parameters, the linear differential equations for small perturbations about the background do not have a growing mode. We also examine the energy of fluctuations about this background in flat-space. If the kinetic terms for the vector field do not take the form of a field strength tensor squared then there is a negative energy mode and the background is unstable. For the case where the kinetic term is of the form of a field strength tensor squared we show that perturbations about the background have positive energy at lowest order.
Cite
@article{arxiv.0801.2950,
title = {Classical stability of a homogeneous, anisotropic inflating space-time},
author = {Timothy R. Dulaney and Moira I. Gresham and Mark B. Wise},
journal= {arXiv preprint arXiv:0801.2950},
year = {2014}
}
Comments
12 pages, no figures; references added, content in section V revised and some clarification made in text; minor typos corrected, v4 closely resembles version published in Phys. Rev. D; in v5 - incorrect argument in section V removed and one reference added