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Entanglement of thermal scalar fields in a compact space space

Jae-Weon Lee·Jaewan Kim·Taeseung Choi
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Abstract

Using the thermal Green's function approach we propose a general method to investigate entanglement of the vacuum state or thermal ground states in an arbitrary dimensional space-time. As an application we show quantum separability of the massive thermal scalar field vacuum in the 1+1 dimensional cylindrical space-time. Separability is demonstrated using the positive partial transpose criterion for effective two-mode Gaussian states of collective operators. In this case, for all mass and temperature values entanglement is absent between the collective operators.

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Jae-Weon Lee, Jaewan Kim, Taeseung Choi. 2007-04-03. Entanglement of thermal scalar fields in a compact space space. https://arxiv.org/abs/quant-ph/0702264

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