Black hole thermodynamics and two-dimensional dilaton gravity theory - art. no. 044013

We relate various black hole solutions in the near-horizon region to black hole solutions in two-dimensional dilaton gravity theories in order to argu e that the thermodynamics of black holes in D greater than or equal to 4 ca n be effectively described by the thermodynamics of black holes in two-dime nsional dilaton gravity theories. We show that the Bekenstein-Hawking entro pies of single-charged dilatonic black holes and dilatonic p branes with an arbitrary dilaton coupling parameter in arbitrary spacetime dimensions are exactly reproduced by the Bekenstein-Hawking entropy of the two-dimensiona l black hole in the associated two-dimensional dilaton gravity model. We co mment that the thermodynamics of a nonextreme stringy four-dimensional blac k hole with four charges and a five-dimensional black hole with three charg es may be effectively described by the thermodynamics of black hole solutio ns with a constant dilaton field in two-dimensional dilaton gravity theorie s.