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Black hole entropy in string-generated gravity models

Ishwaree P. Neupane
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Abstract

The Euclidean action and entropy are computed in string-generated gravity models with quadratic curvatures, and used to argue that a negative mass extremal metric is the background for hyperbolic (k=-1) black hole spacetimes, k being the curvature constant of the event horizon. The entropy associated with a black hole is always positive for k=(0,1) family. The positivity of energy condition also ensures that the k=-1 (extremal) entropy is non-negative.

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Ishwaree P. Neupane. 2003-02-17. Black hole entropy in string-generated gravity models. https://doi.org/10.1103/physrevd.67.061501

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