Towards Anisotropy-Free and Non-Singular Bounce Cosmology with Scale-invariant Perturbations
Abstract
We investigate non-singular bounce realizations in the framework of ghost-free generalized Galileon cosmology, which furthermore can be free of the anisotropy problem. Considering an Ekpyrotic-like potential we can obtain a total Equation-of-State (EoS) larger than one in the contracting phase, which is necessary for the evolution to be stable against small anisotropic fluctuations. Since such a large EoS forbids the Galileon field to generate the desired form of perturbations, we additionally introduce the curvaton field which can in general produce the observed nearly scale-invariant spectrum. In particular, we provide approximate analytical and exact semi-analytical expressions under which the bouncing scenario is consistent with observations. Finally, the combined Galileon-curvaton system is free of the Big-Rip after the bounce.
Keywords
Cite
@article{arxiv.1303.2372,
title = {Towards Anisotropy-Free and Non-Singular Bounce Cosmology with Scale-invariant Perturbations},
author = {Taotao Qiu and Xian Gao and Emmanuel N. Saridakis},
journal= {arXiv preprint arXiv:1303.2372},
year = {2013}
}
Comments
13 pages, 9 figures