Cosmic Acceleration Driven by Mirage Inhomogeneities
Abstract
A cosmological model based on an inhomogeneous D3-brane moving in an AdS_5 X S_5 bulk is introduced. Although there is no special points in the bulk, the brane Universe has a center and is isotropic around it. The model has an accelerating expansion and its effective cosmological constant is inversely proportional to the distance from the center, giving a possible geometrical origin for the smallness of a present-day cosmological constant. Besides, if our model is considered as an alternative of early time acceleration, it is shown that the early stage accelerating phase ends in a dust dominated FRW homogeneous Universe. Mirage-driven acceleration thus provides a dark matter component for the brane Universe final state. We finally show that the model fulfills the current constraints on inhomogeneities.
Keywords
Cite
@article{arxiv.hep-th/0509136,
title = {Cosmic Acceleration Driven by Mirage Inhomogeneities},
author = {Christophe Galfard and Cristiano Germani and Alex Kehagias},
journal= {arXiv preprint arXiv:hep-th/0509136},
year = {2009}
}
Comments
14 pages, 1 figure, IOP style. v2, changed style, minor corrections, references added, version accepted in Class. Quant. Grav