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Dynamical Origin of the Entropy of a Black Hole

Valery Frolov·Igor Novikov
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Abstract

Modes of physical fields which are located inside a horizon and which cannot be observed by a distant observer are identified with dynamical degrees of freedom of a black hole. A new invariant statistical mechanical definition of a black-hole's entropy is proposed. It is shown that the main contribution to the entropy is given by thermally excited `invisible' modes propagating in the close vicinity of the horizon. A calculation based on the proposed definition yields a value of the entropy which is in good agreement with the usually adopted value.

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Valery Frolov, Igor Novikov. 2020-12-31. Dynamical Origin of the Entropy of a Black Hole. https://doi.org/10.1103/physrevd.48.4545

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