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arXiv · hep-th/9708014

Entropy and Topology for Gravitational Instantons

Stefano Liberati·Giuseppe Pollifrone
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Abstract

In this work a relation between topology and thermodynamical features of gravitational instantons is shown. The expression for the Euler characteristic, through the Gauss-Bonnet integral, and the one for the entropy of gravitational instantons are proposed in a form that makes the relation between them self-evident. A new formulation of the Bekenstein-Hawking formula, where the entropy and the Euler characteristic are related by $S=χA/8$, is obtained. This formula provides the correct results for a wide class of gravitational instantons described by both spherically and axially symmetric metrics.

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Stefano Liberati, Giuseppe Pollifrone. 1997-08-04. Entropy and Topology for Gravitational Instantons. https://doi.org/10.1103/physrevd.56.6458

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