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arXiv · 2105.02598

Non-Gaussianity of Entanglement Entropy and Correlations of Composite Operators

Satoshi Iso·Takato Mori·Katsuta Sakai
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Abstract

This is an extended version of the previous paper arXiv:2103.05303 to study entanglement entropy (EE) of a half space in interacting field theories. In the previous paper, we have proposed a novel method to calculate EE based on the notion of $\mathbb{Z}_M$ gauge theory on Feynman diagrams, and shown that EE consists of two particular contributions, one from a renormalized two-point correlation function in the two-particle irreducible (2PI) formalism and another from interaction vertices. In this paper, we further investigate them in more general field theories and show that the non-Gaussian contributions from vertices can be interpreted as renormalized correlation functions of composite operators.

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Satoshi Iso, Takato Mori, Katsuta Sakai. 2021-05-06. Non-Gaussianity of Entanglement Entropy and Correlations of Composite Operators. https://doi.org/10.1103/physrevd.103.125019

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