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Entropy of semiclassical 2D dilaton black holes away from the Hawking temperature

O. B. Zaslavskii
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Abstract

Recently we showed that in semiclassical 2D dilaton gravity the regularity of a black hole horizon may be compatible with divergencies of Polyakov-Liouville stresses on it, the temperature deviating from its Hawking value. This makes the question about thermal properties of such solutions non-trivial. We demonstrate that, adding to gravitation-dilaton part of the action certain counterterms, which diverge on the horizon but are finite outside it, one may achieve finiteness of the effective gravitation-dilaton couplings on the horizon. This gives for the entropy S the Bekenstein - Hawking value in the nonextreme case and S=0 in the extreme one similarly to what happens to ''standard '' black holes.

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O. B. Zaslavskii. 2002-08-28. Entropy of semiclassical 2D dilaton black holes away from the Hawking temperature. https://doi.org/10.1142/s0217732302008198

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