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Published on: May 27, 2020
Entanglement Entropy after Double Excitation as an Interaction Measure
Yuya Kusuki1, Masamichi Miyaji2
1Center for Gravitational Physics, Yukawa Institute for Theoretical Physics (YITP), Kyoto University, Kitashirakawa Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Abstract:
We study entanglement entropy after a double local quench in two-dimensional conformal field theories (CFTs). In the holographic CFT, such a state with double excitation is dual to an anti-de Sitter space with two massive particles injected from the boundary. We show that the growth after the double local excitations in pure CFT is universal and is given by the sum of two local quenches with an additional negative term. This negative contribution can be interpreted naturally in holography as being due to the attractive force of gravity. On the CFT side, this evaluation of the entanglement entropy is accomplished by a special limit of six-point functions, where we employ the fusion matrix approach for multipoint conformal blocks developed by the authors [J. High Energy Phys. 08 (2019) 063JHEPFG1029-847910.1007/JHEP08(2019)063].
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