This is an extended version of the previous paper [S. Iso et al., Phys. Rev. D 103, 105010 (2021)] 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.

中文翻译：

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纠缠熵的非高斯性和复合算子的相关性

这是上一篇论文 [S. 伊索等人。，物理。Rev. D 103 , 105010 (2021)] 研究相互作用场论中半空间的纠缠熵 (EE)。在之前的论文中，我们提出了一种基于概念的计算 EE 的新方法${\mathbb{Z}}_{米}$费曼图上的规范理论，并表明 EE 由两个特殊贡献组成，一个来自双粒子不可约 (2PI) 形式主义中的重整化两点相关函数，另一个来自相互作用顶点。在本文中，我们在更一般的场论中进一步研究它们，并表明顶点的非高斯贡献可以解释为复合算子的重整化相关函数。