Palestrante: Steve Carlip (University of California Davis)

Resumo: One of the basic puzzles of black hole thermodynamics is the simplicity and universality of the Bekenstein-Hawking entropy. The idea that this entropy might be governed by a symmetry at the horizon is an old one, but until now efforts have focused on conformal symmetries, either at infinity or on a "stretched horizon." I argue that a better approach uses a BMS-like symmetry of the horizon itself. This avoids the limitations of previous attempts (including my own), and explains the entropy in terms of a generalization of the Cardy formula for the density of states.