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arXiv · 2403.08467

Uniqueness of extremal charged black holes in de Sitter

David Katona
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Abstract

We prove a uniqueness theorem for the charged Nariai black holes and ultracold black holes in four dimensions. In particular, we show that an analytic solution to four-dimensional Einstein-Maxwell theory with a positive cosmological constant containing a static extremal Killing horizon with spherical cross-sections of large radius (compared to the cosmological scale), must be locally isometric to the extremal Reissner-Nordstr\"om-de Sitter black hole or its near-horizon geometry. The theorem generalises to extremal static horizons with small radius, establishing uniqueness of cold black holes for generic values of the radius.

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David Katona. 2024-03-13. Uniqueness of extremal charged black holes in de Sitter. https://doi.org/10.1088/1361-6382/ad7a49

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