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arXiv · 1708.03627

Nonexistence of Extremal de Sitter Black Rings

Marcus Khuri·Eric Woolgar
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Abstract

We show that near-horizon geometries in the presence of a positive cosmological constant cannot exist with ring topology. In particular, de Sitter black rings with vanishing surface gravity do not exist. Our result relies on a known mathematical theorem which is a straightforward consequence of a type of energy condition for a modified Ricci tensor, similar to the curvature-dimension conditions for the $m$-Bakry-Émery-Ricci tensor.

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Marcus Khuri, Eric Woolgar. 2017-08-14. Nonexistence of Extremal de Sitter Black Rings. https://doi.org/10.1088/1361-6382%2Faa9154

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