Gauge-invariant gravitational wave modes in pre-big bang cosmology
General Relativity and Quantum Cosmology
2011-02-09 v1 High Energy Physics - Theory
Abstract
The t<0 branch of pre-big bang cosmological scenarios is subject to a gravitational wave instability. The unstable behaviour of tensor perturbations is derived in a very simple way in Hwang's covariant and gauge-invariant formalism developed for extended theories of gravity. A simple interpretation of this instability as the effect of an "antifriction" is given, and it is argued that a universe must eventually enter the expanding phase.
Cite
@article{arxiv.1009.0660,
title = {Gauge-invariant gravitational wave modes in pre-big bang cosmology},
author = {Valerio Faraoni},
journal= {arXiv preprint arXiv:1009.0660},
year = {2011}
}
Comments
4 pages, latex, to appear in Eur. Phys. J. C