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arXiv · 2412.05381

The boundary entropy function for interface conformal field theories

Evangelos Afxonidis·Andreas Karch·Chitraang Murdia
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Abstract

{In 1+1 dimensional conformal field theory with a boundary the boundary contribution to the entanglement entropy is determined by a single number $g$ effectively counting the boundary degrees of freedom. In contrast, in 1+1 dimensional interface CFTs the corresponding quantity is a non-trivial {\it function} depending on the position of the interval relative to the interface, giving access to much more detailed information about the defect. In this work we determined this $g$-function in several examples using holography and derive some of its basic properties from holography and strong subadditivity.

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Evangelos Afxonidis, Andreas Karch, Chitraang Murdia. 2024-12-06. The boundary entropy function for interface conformal field theories. https://arxiv.org/abs/2412.05381

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