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arXiv · 2407.07824

Entanglement Entropy as a Probe Beyond the Horizon

Konstantinos Boutivas·Dimitrios Katsinis·Georgios Pastras·Nikolaos Tetradis
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Abstract

The entanglement entropy of a free field in de Sitter space is enhanced by the squeezing of its modes. We show analytically that the expansion induces a term in the entanglement entropy that depends logarithmically on the size of the overall system, which may extend beyond the horizon. In cosmology the size of the system can be identified with the size of a spatially finite universe, or with the wavelength of the first mode that exited the horizon in the beginning of inflation.

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Konstantinos Boutivas, Dimitrios Katsinis, Georgios Pastras, Nikolaos Tetradis. 2024-07-10. Entanglement Entropy as a Probe Beyond the Horizon. https://arxiv.org/abs/2407.07824

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