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arXiv · 1210.7244

Entanglement entropy in de Sitter space

Juan Maldacena·Guilherme L. Pimentel
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Abstract

We compute the entanglement entropy for some quantum field theories on de Sitter space. We consider a superhorizon size spherical surface that divides the spatial slice into two regions, with the field theory in the standard vacuum state. First, we study a free massive scalar field. Then, we consider a strongly coupled field theory with a gravity dual, computing the entanglement using the gravity solution. In even dimensions, the interesting piece of the entanglement entropy is proportional to the number of e-foldings that elapsed since the spherical region was inside the horizon. In odd dimensions it is contained in a certain finite piece. In both cases the entanglement captures the long range correlations produced by the expansion.

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Juan Maldacena, Guilherme L. Pimentel. 2012-11-28. Entanglement entropy in de Sitter space. https://doi.org/10.1007/jhep02(2013)038

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