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arXiv · 1703.01611

Instantons and Entanglement Entropy

Arpan Bhattacharyya·Ling-Yan Hung·Charles M. Melby-Thompson
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Abstract

We would like to put the area law -- believed to by obeyed by entanglement entropies in the ground state of a local field theory -- to scrutiny in the presence of non-perturbative effects. We study instanton corrections to entanglement entropy in various models whose instanton effects are well understood, including $U(1)$ gauge theory in 2+1 dimensions and false vacuum decay in $ϕ^4$ theory, and we demonstrate that the area law is indeed obeyed in these models. We also perform numerical computations for toy wavefunctions mimicking the theta vacuum of the (1+1)-dimensional Schwinger model. Our results indicate that such superpositions exhibit no more violation of the area law than the logarithmic behavior of a single Fermi surface.

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Arpan Bhattacharyya, Ling-Yan Hung, Charles M. Melby-Thompson. 2017-12-05. Instantons and Entanglement Entropy. https://doi.org/10.1007/jhep10(2017)081

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