Black Hole Entropy and the Problem of Universality
arXiv:gr-qc/0702094 · doi:10.1088/1742-6596/67/1/012022
Abstract
A key test of any quantum theory of gravity is its ability to reproduce the known thermodynamic properties of black holes. A statistical mechanical description of the Bekenstein-Hawking entropy once seemed remote, but today we suffer an embarrassment of riches: many different approaches to quantum gravity yield the same entropy, despite counting very different states. This ``universality'' suggests that some underlying feature of the classical theory may control the quantum density of states. I discuss the possibility that this feature is an approximate two-dimensional conformal symmetry near the horizon.
10 pages, LaTeX; talk at DICE 2006, Piombino, Italy