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arXiv · 2103.05303

Entanglement entropy in scalar field theory and $\mathbb{Z}_M$ gauge theory on Feynman diagrams

Satoshi Iso·Takato Mori·Katsuta Sakai
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Abstract

Entanglement entropy (EE) in interacting field theories has two important issues: renormalization of UV divergences and non-Gaussianity of the vacuum. In this letter, we investigate them in the framework of the two-particle irreducible formalism. In particular, we consider EE of a half space in an interacting scalar field theory. It is formulated as $\mathbb{Z}_M$ gauge theory on Feynman diagrams: $\mathbb{Z}_M$ fluxes are assigned on plaquettes and summed to obtain EE. Some configurations of fluxes are interpreted as twists of propagators and vertices. The former gives a Gaussian part of EE written in terms of a renormalized 2-point function while the latter reflects non-Gaussianity of the vacuum.

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Satoshi Iso, Takato Mori, Katsuta Sakai. 2021-03-09. Entanglement entropy in scalar field theory and $\mathbb{Z}_M$ gauge theory on Feynman diagrams. https://doi.org/10.1103/physrevd.103.105010

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