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arXiv · 2112.03922

Islands and the de Sitter entropy bound

Daniele Teresi
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Abstract

The de Sitter (dS) entropy bound gives the maximal number of e-folds that non-eternal inflation can last before violating the thermodynamical interpretation of dS space. This semiclassical argument is the analogue, for dS space, of the Black-Hole information paradox. We use techniques developed to address the latter, namely the island formula, to calculate semiclassically the fine-grained entropy as seen by a Minkowskian observer after inflation and find that this follows a Page-like curve, never exceeding the thermodynamic dS entropy. This calculation, performed for a CFT in 2D gravity, suggests that the semiclassical expectation should be modified in such a way that the entropy bound might actually not be present.

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Daniele Teresi. 2021-12-07. Islands and the de Sitter entropy bound. https://doi.org/10.1007/jhep10(2022)179

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