Black hole entropy from conformal field theory in any dimension

Restricted to a black hole horizon, the "gauge" algebra of surface deformat ions in general relativity contains a Virasoro subalgebra with a calculable central charge. The fields in any quantum theory of gravity must transform accordingly, i.e., they must admit a conformal field theory description. A pplying Cardy's formula for the asymptotic density of states, I use this re sult to derive the Bekenstein-Hawking entropy. This method is universal-it holds for any black hole, and requires no details of quantum gravity-but it is also explicitly statistical mechanical, based on counting microscopic s tates. [S0031-9007(99)08779-7].