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Hartle-Hawking state is a maximum of entanglement entropy

Shinji Mukohyama
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Abstract

It is shown that the Hartle-Hawking state of a scalar field is a maximum of entanglement entropy in the space of pure quantum states satisfying the condition that backreaction is finite. In other words, the Hartle-Hawking state is a curved-space analogue of the EPR state, which is also a maximum of entanglement entropy.

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BibTeXRIS

Shinji Mukohyama. 1999-08-26. Hartle-Hawking state is a maximum of entanglement entropy. https://doi.org/10.1103/physrevd.61.064015

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