1204.1284 (Alejandra Castro et al.)

Universal properties and the first law of black hole inner mechanics    [PDF]

Alejandra Castro, Maria J. Rodriguez

We show by explicit computations that the product of all the horizon areas is independent of the mass, regardless of the topology of the horizons. The universal character of this relation holds for all known five dimensional asymptotically flat black rings, and black strings. This gives further evidence on the crucial role that the thermodynamic properties at each horizon plays in understanding the entropy at the microscopic level. To this end we propose a "first law" for the inner Cauchy horizons of black holes. The validity of this formula, which seems to be universal, was explicitly checked in all cases.

View original: http://arxiv.org/abs/1204.1284