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arXiv · 2312.08353

Boundary Conditions for Extremal Black Holes from 2d Gravity

Stéphane Detournay·Thomas Smoes·Raphaela Wutte
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Abstract

We devise new boundary conditions for the near-horizon geometries of extremal BTZ and Kerr black holes, as well as for the ultra-cold limit of the Kerr-de Sitter black hole. These boundary conditions are obtained as the higher-dimensional uplift of recently proposed boundary conditions in two-dimensional gravity. Their asymptotic symmetries consist in the semi-direct product of a Virasoro and a current algebra, of which we determine the central extensions.

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Stéphane Detournay, Thomas Smoes, Raphaela Wutte. 2023-12-13. Boundary Conditions for Extremal Black Holes from 2d Gravity. https://arxiv.org/abs/2312.08353

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