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arXiv · 1010.6175

Brane singularities and their avoidance

I. Antoniadis·S. Cotsakis·I. klaoudatou
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Abstract

The singularity structure and the corresponding asymptotic behavior of a 3-brane coupled to a scalar field or to a perfect fluid in a five-dimensional bulk is analyzed in full generality using the method of asymptotic splittings. In the case of the scalar field, it is shown that the collapse singularity at a finite distance from the brane can be avoided only at the expense of making the brane world-volume positively or negatively curved. In the case where the bulk field content is parametrized by an analogue of perfect fluid with an arbitrary equation of state P=γρbetween the `pressure' P and the `density' ρ, our results depend crucially on the constant fluid parameter γ: (i) For γ>-1/2, the flat brane solution suffers from a collapse singularity at finite distance, that disappears in the curved case. (ii) For γ<-1, the singularity cannot be avoided and it becomes of the big rip type for a flat brane. (iii) For -1<γ< or = -1/2, the surprising result is found that while the curved brane solution is singular, the flat brane is not, opening the possibility for a revival of the self-tuning proposal.

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I. Antoniadis, S. Cotsakis, I. klaoudatou. 2010-10-29. Brane singularities and their avoidance. https://doi.org/10.1088/0264-9381%2F27%2F23%2F235018

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