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arXiv · 2310.06054

Perturbative Method for Mutual Information and Thermal Entropy of Scalar Quantum Fields

Joseph Bramante·Andrew Buchanan
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Abstract

A new approach is presented to compute entropy for massless scalar quantum fields. By perturbing a skewed correlation matrix composed of field operator correlation functions, the mutual information is obtained for disjoint spherical regions of size $r$ at separation $R$, including an expansion to all orders in $r/R$. This approach also permits a perturbative expansion for the thermal field entropy difference in the small temperature limit ($T \ll 1/r$).

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Joseph Bramante, Andrew Buchanan. 2023-10-09. Perturbative Method for Mutual Information and Thermal Entropy of Scalar Quantum Fields. https://arxiv.org/abs/2310.06054

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