Non-singular Cyclic Cosmology without Phantom Menace
Abstract
In this article we review recent developments of cyclic cosmology. A typical non-singular cyclic model within General Relativity requires a non-conventional fluid with negative effective energy density, in order to cancel the matter component and lead to a non-singular bounce. However, the existence of such a non-conventional fluid usually leads to quantum instabilities and makes the theory ill-defined. In the present work we follow the alternative way, obtaining two scenarios of non-singular cyclic cosmological evolutions in the context of gravitational theories beyond General Relativity. The degrees-of-freedom examination reveals that these two models are free of the Phantom Menace. Our analysis illustrates that, if cyclic cosmology describes overall universe, a theory of gravity beyond Einstein may be expected.
Cite
@article{arxiv.1108.6052,
title = {Non-singular Cyclic Cosmology without Phantom Menace},
author = {Yi-Fu Cai and Emmanuel N. Saridakis},
journal= {arXiv preprint arXiv:1108.6052},
year = {2012}
}
Comments
16 pages, 2 figures, to appear in Journal of Cosmology