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arXiv:1906.00641

Perturbative calculation of field space entanglement entropy

Brister, James

Published Jun 3, 2019• 0 citations
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Abstract

We present a general method for the perturbative calculation of the entanglement entropy between two interacting quantum fields. Previous attempts at calculating this quantity perturbatively have encountered a seemingly pathological divergence; we explain why this divergence is a result of improperly truncating a series expansion and give a prescription for avoiding this problem. We then apply our method to a simple example of two mass-mixing scalar fields.

DOI
10.48550/arxiv.1906.00641

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We present a general method for the perturbative calculation of the entanglement entropy between two interacting quantum fields. Previous attempts at calculating this quantity perturbatively have encountered a seemingly pathological divergence; we explain why this divergence is a result of improperly truncating a series expansion and give a prescription for avoiding this problem. We then apply our method to a simple example of two mass-mixing scalar fields.
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