Creating the Universe from Brane-Antibrane Annihilation

When p-dimensional branes annihilate with antibranes in the early universe, as in brane-antibrane inflation, stable (p-2)-dimensional branes can appear in the final state. We reexamine the possibility that one of these (p-2)-branes could be our universe. In the low energy effective theory, the final state branes are cosmic string defects of the complex tachyon field which describes the instability of the initial state. We quantify the dynamics of formation of these vortices. This information is then used to estimate the production of massless gauge bosons on the final branes, due to their coupling to the time-dependent tachyon background, which would provide a mechanism for reheating after inflation. We improve upon previous estimates indicating that this can be an efficient reheating mechanism for observers on the brane.