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Closed universes in two dimensional gravity

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arxiv 2402.00098 v3 pith:I76VHGY4 submitted 2024-01-31 hep-th gr-qcquant-ph

classification hep-thgr-qcquant-ph
keywords closedgravitydimensionalfindnon-perturbativetheorythereuniverses
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We study closed universes in simple models of two dimensional gravity, such as Jackiw-Teiteilboim (JT) gravity coupled to matter, and a toy topological model that captures the key features of the former. We find there is a stark contrast, as well as some connections, between the perturbative and non-perturbative aspects of the theory. We find rich semi-classical physics. However, when non-perturbative effects are included there is a unique closed universe state in each theory. We discuss possible meanings and interpretations of this observation.

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Cited by 15 Pith papers

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