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arXiv · 2103.13422

From black holes to baby universes in CGHS gravity

Victor Godet·Charles Marteau
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Abstract

We study $\widehat{\text{CGHS}}$ gravity, a variant of the matterless Callan-Giddings-Harvey-Strominger model. We show that it describes a universal sector of the near horizon perturbations of non-extremal black holes in higher dimensions. In many respects this theory can be viewed as a flat space analog of Jackiw-Teitelboim gravity. The result for the Euclidean path integral implies that $\widehat{\text{CGHS}}$ is dual to a Gaussian ensemble that we describe in detail. The simplicity of this theory allows us to compute exact quantities such as the quenched free energy and provides a useful playground to study baby universes, averages and factorization. We also give evidence for the existence of a non-perturbative completion in terms of a matrix model. Finally, flat wormhole solutions are discussed.

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Victor Godet, Charles Marteau. 2021-03-24. From black holes to baby universes in CGHS gravity. https://doi.org/10.1007/jhep07(2021)138

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