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arXiv · 1709.03205

On the Renormalization of Entanglement Entropy

Jiunn-Wei Chen·Jin-Yi Pang
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Abstract

The renormalization of entanglement entropy of quantum field theories is investigated in the simplest setting with a $\lambda \phi^4$ scalar field theory. The 3+1 dimensional spacetime is separated into two regions by an infinitely flat 2-dimensional interface. The entanglement entropy of the system across the interface has an elegant geometrical interpretation using the replica trick, which requires putting the field theory on a curved spacetime background. We demonstrate that the theory, and hence the entanglement entropy, is renormalizable at order $\lambda$ once all the relevant operators up to dimension-4 are included in the action. This exercise has a one-to-one correspondence to entanglement entropy interpretation of the black hole entropy which suggests that our treatment is sensible. Our study suggests that entanglement entropy is renormalizable and is a physical quantity.

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Jiunn-Wei Chen, Jin-Yi Pang. 2017-09-11. On the Renormalization of Entanglement Entropy. https://arxiv.org/abs/1709.03205

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