Brane cosmology with an anisotropic bulk
Abstract
In the context of brane cosmology, a scenario where our universe is a 3+1-dimensional surface (the ``brane'') embedded in a five-dimensional spacetime (the ``bulk''), we study geometries for which the brane is anisotropic - more specifically Bianchi I - though still homogeneous. We first obtain explicit vacuum bulk solutions with anisotropic three-dimensional spatial slices. The bulk is assumed to be empty but endowed with a negative cosmological constant. We then embed Z_2-symmetric branes in the anisotropic spacetimes and discuss the constraints on the brane energy-momentum tensor due to the five-dimensional anisotropic geometry. We show that if the bulk is static, an anisotropic brane cannot support a perfect fluid. However, we find that for some of our bulk solutions it is possible to embed a brane with a perfect fluid though its energy density and pressure are completely determined by the bulk geometry.
Cite
@article{arxiv.hep-th/0407262,
title = {Brane cosmology with an anisotropic bulk},
author = {A. Fabbri and D. Langlois and D. A. Steer and R. Zegers},
journal= {arXiv preprint arXiv:hep-th/0407262},
year = {2010}
}
Comments
20 pages, 1 figure