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arXiv · 2401.00219

Entanglement Entropy via Double Cone Regularization

Taishi Kawamoto·Yu-ki Suzuki
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Abstract

This paper proposes an alternative regularization method for handling the ultraviolet behavior of entanglement entropy. Utilizing an $i\epsilon$ prescription in the Euclidean double cone geometry, it accurately reproduces the universal behavior of entanglement entropy. The method is demonstrated in the free boson theory in arbitrary dimensions and two-dimensional conformal field theories. The findings highlight the effectiveness of the $i\epsilon$ regularization method in addressing ultraviolet issues in quantum field theory and gravity, suggesting potential applications to other calculable quantities.

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Taishi Kawamoto, Yu-ki Suzuki. 2023-12-30. Entanglement Entropy via Double Cone Regularization. https://arxiv.org/abs/2401.00219

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