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arXiv · 2510.01655

Entanglement entropy between tangent balls in CFT$_D$

Jiankun Li·Li Song
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Abstract

We apply the universal method developed in \cite{Jiang:2025jnk} to compute the entanglement entropy between two tangent balls in CFT$_D$. When taking the radius of one ball to infinity, it gives the entanglement entropy between a ball and its tangent half plane. In two-dimensional case, this configuration is equivalent to the entanglement in boundary conformal field theory (BCFT) between the negative half-axis and an interval ending on the boundary.

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Jiankun Li, Li Song. 2025-10-02. Entanglement entropy between tangent balls in CFT$_D$. https://arxiv.org/abs/2510.01655

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