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arXiv:2507.01174 · Physical review. D/Physical review. D.

Entanglement on a sphere

Konstantinos Boutivas, Dimitrios Katsinis, Georgios Pastras, Nikolaos Prountzos, N. Tetradis

Published Sep 9, 2025• 1 citation
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Abstract

We study the entanglement entropy of a massive scalar field in the background of the Einstein universe. We determine numerically the structure of the UV-divergent terms. We study analytically the IR term that originates in the long-range correlations arising from the field zero mode on the sphere. We compare with previous results for a scalar field in a de Sitter or an anti–de Sitter background.

DOI
10.1103/8h9z-gmnm

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