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arXiv · 2502.03869

A microscopic model of de Sitter spacetime with an observer

Damiano Tietto·Herman Verlinde
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Abstract

We introduce a simple microscopic quantum mechanical model of low-dimensional de Sitter holography with an observer. Using semiclassical gravity and elementary thermodynamic considerations, we derive a formula for the total entropy of a 3D Schwarzschild-de Sitter universe with an observer. We then match this entropy formula with the exactly known spectral density of the double scaled SYK model. Our result gives a de Sitter interpretation of the appearance of two notions of temperature in DSSYK.

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Damiano Tietto, Herman Verlinde. 2025-02-06. A microscopic model of de Sitter spacetime with an observer. https://arxiv.org/abs/2502.03869

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