S-Branes, Negative Tension Branes and Cosmology

Abstract

A general class of solutions of string background equations is studied and its physical interpretations are presented. These solutions correspond to generalizations of the standard black p-brane solutions to surfaces with curvature k=-1,0. The relation with the recently introduced S-branes is provided. The mass, charge, entropy and Hawking temperature are computed, illustrating the interpretation in terms of negative tension branes. Their cosmological interpretation is discussed as well as their potential instability under small perturbations.

10 pages. Talks given at: SUSY'02, ``the 10th International Conference on Supersymmetry and Unification of Fundamental Interactions'', DESY, Hamburg, Germany, 17-23 June 2002, and ``The 1st International Conference on String Phenomenology'', Oxford, July 6 - 11, 2002. References added