Strings from geometric tachyon in Rindler space and black hole thermodynamics

Abstract

The dynamics of a probe particle or wrapped brane moving in the two-dimensional Rindler space can be described by a time-dependent tachyon field theory. Using knowledge of tachyon condensation, we learn that the infalling brane gets thermalised and produces open string pairs at the Hagedorn temperature when entering into the near-horizon Rindler wedge. It is shown that the Hagedorn temperature of the infalling brane is equal to the Hawking temperature of the host black hole detected in the same time coordinate. The infalling brane will decay completely into closed strings, mainly massive modes, when it reaches the horizon in infinitely long time as observed by observers at spatial infinity. Preliminary estimates indicate that the degeneracy of states of the closed strings emitted from the infalling brane should be responsible for the increased entropy in the host black hole due to absorption of the brane.