Exploring the entanglement of free spin-(1/2), spin-1 and spin-2 fields

作     者：Zhi Yang Ling-Yan Hung 杨智;孔令欣

作者机构：Department of Physics & Center for Field Theory and Particle Physics Fudan University State Key Laboratory of Surface Physics & Department of Physics Fudan University 

出 版 物：《Chinese Physics C》 (中国物理C（英文版）)

年 卷 期：2019年第43卷第5期

页      面：12-22页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Supported by the NSFC(11875111) 

主　　题：entanglement Bogoliubov transformation tensor product structure 

摘      要：In this study, we explore the entanglement of free spin-(1/2), spin-1, and spin-2 fields. We start with an example involving Majorana fields in 1+1 and 2+1 dimensions. Subsequently, we perform the Bogoliubov transformation and express the vacuum state with a particle pair state in the configuration space, which is used to calculate the entropy. This clearly demonstrates that the entanglement entropy originates from the particles across the ***, we generalize this method to free spin-1 and spin-2 fields. These higher free massless spin fields have wellknown complications owing to gauge redundancy. We deal with the redundancy by gauge-fixing in the light-cone gauge. We show that this gauge provides a natural tensor product structure in the Hilbert space, while surrendering explicit Lorentz invariance. We also use the Bogoliubov transformation to calculate the entropy. The area law emerges naturally by this method.