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arXiv · hep-th/0207104

Cosmological Spacetimes from Negative Tension Brane Backgrounds

C. P. Burgess·F. Quevedo·S. -J. Rey·G. Tasinato·I. Zavala
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Abstract

We identify a time-dependent class of metrics with potential applications to cosmology, which emerge from negative-tension branes. The cosmology is based on a general class of solutions to Einstein-dilaton-Maxwell theory, presented in {hep-th/0106120}. We argue that solutions with hyperbolic or planar symmetry describe the gravitational interactions of a pair of negative-tension $q$-branes. These spacetimes are static near each brane, but become time-dependent and expanding at late epoch -- in some cases asymptotically approaching flat space. We interpret this expansion as being the spacetime's response to the branes' presence. The time-dependent regions provide explicit examples of cosmological spacetimes with past horizons and no past naked singularities. The past horizons can be interpreted as S-branes. We prove that the singularities in the static regions are repulsive to time-like geodesics, extract a cosmological `bounce' interpretation, compute the explicit charge and tension of the branes, analyse the classical stability of the solution (in particular of the horizons) and study particle production, deriving a general expression for Hawking's temperature as well as the associated entropy.

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C. P. Burgess, F. Quevedo, S. -J. Rey, G. Tasinato, I. Zavala. 2002-12-07. Cosmological Spacetimes from Negative Tension Brane Backgrounds. https://doi.org/10.1088/1126-6708%2F2002%2F10%2F028

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