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arXiv · 0705.2478

Entropy of an extremal regular black hole

Yun Soo Myung·Yong-Wan Kim·Young-Jai Park
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Abstract

We introduce a magnetically charged extremal regular black hole in the coupled system of Einstein gravity and nonlinear electrodynamics. Its near horizon geometry is given by $AdS_2\times S^2$. It turns out that the entropy function approach does not automatically lead to a correct entropy of the Bekenstein-Hawking entropy. This contrasts to the case of the extremal Reissner-Norström black hole in the Einstein-Maxwell theory. We conclude that the entropy function approach does not work for a magnetically charged extremal regular black hole without singularity, because of the nonlinearity of the entropy function.

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Yun Soo Myung, Yong-Wan Kim, Young-Jai Park. 2007-12-10. Entropy of an extremal regular black hole. https://doi.org/10.1016/j.physletb.2007.12.007

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