Entropy of Reissner-Nordström-like black holes

Abstract

In Poincaré gauge theory, black hole entropy is defined canonically by the variation of a boundary term ΓH, located at horizon. For a class of static and spherically symmetric black holes in vacuum, the explicit formula reads δΓH=TδS, where T is black hole temperature and S entropy. Here, we analyze a new member of the same class, the Reissner-Nordström-like black hole with torsion [1], where the electric charge of matter is replaced by a gravitational parameter, induced by the existence of torsion. This parameter affects δΓH in a way that ensures the validity of the first law.