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Solution Independent Analysis of Black Hole Entropy in Brick Wall Model

M. Kenmoku·K. K. Nandi·K. Shigemoto
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Abstract

Using the brick wall regularization of 't Hooft, the entropy of non-extreme and extreme black holes is investigated in a general static, spherically symmetric spacetime. We classify the singularity in the entropy by introducing a {\it new} index $δ$ with respect to the brick wall cut-off $ε$. The leading contribution to entropy for non-extreme case $(δ\neq 0)$ is shown to satisfy the area law with quadratic divergence with respect to the invariant cut-off $ε_{\rm inv}$ while the extreme case $(δ=0)$ exhibits logarithmic divergence or constant value with respect to $ε$. The general formula is applied to Reissner-Nordström, dilaton and brane-world black holes and we obtain consistent results.

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M. Kenmoku, K. K. Nandi, K. Shigemoto. 2007-06-06. Solution Independent Analysis of Black Hole Entropy in Brick Wall Model. https://doi.org/10.1088/0264-9381%2F22%2F19%2F008

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