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arXiv · 0907.3568

Extremal black holes in the Hořava-Lifshitz gravity

Hyung Won Lee·Yong-Wan Kim·Yun Soo Myung
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Abstract

We study the near-horizon geometry of extremal black holes in the $z=3$ Hořava-Lifshitz gravity with a flow parameter $λ$. For $λ>1/2$, near-horizon geometry of extremal black holes are AdS$_2 \times S^2$ with different radii, depending on the (modified) Hořava-Lifshitz gravity. For $1/3\le λ\le 1/2$, the radius $v_2$ of $S^2$ is negative, which means that the near-horizon geometry is ill-defined and the corresponding Bekenstein-Hawking entropy is zero. We show explicitly that the entropy function approach does not work for obtaining the Bekenstein-Hawking entropy of extremal black holes.

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Hyung Won Lee, Yong-Wan Kim, Yun Soo Myung. 2010-05-11. Extremal black holes in the Hořava-Lifshitz gravity. https://doi.org/10.1140/epjc%2Fs10052-010-1344-0

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