de Sitter JT gravity from double-scaled SYK

Kazumi Okuyama

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arXiv · 2505.08116

de Sitter JT gravity from double-scaled SYK

Kazumi Okuyama

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Abstract

It is known that the double-scaled SYK model (DSSYK) reduces to JT gravity with a negative cosmological constant by zooming in on the lower edge $E=-E_0$ of the spectrum. We find that the de Sitter JT gravity (i.e. JT gravity with a positive cosmological constant) is reproduced from DSSYK by taking a scaling limit around the upper edge $E=E_0$ of the spectrum. We also argue that the appearance of de Sitter JT gravity is consistent with the behavior of the classical solution of the sine dilaton gravity.

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Kazumi Okuyama. 2025-05-12. de Sitter JT gravity from double-scaled SYK. https://arxiv.org/abs/2505.08116

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