Cosmological Spacetimes from Negative Tension Brane Backgrounds

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 …