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arXiv · 1501.07590

On entanglement entropy in 't Hooft model

Mikhail Goykhman
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Abstract

We use the replica trick approach to calculate, in the large-N limit, the entanglement c-function in two-dimensional quantum chromodynamics with the gauge group U(N) and quark in the fundamental representation ('t Hooft model). We show explicitly that the result is equal to a sum (with certain numerical coefficients) of entanglement c-functions of free massive scalars, which represent mesons in spectrum of the 't Hooft model. Interestingly, each meson contributes as a point-like particle. We provide an explanation for why this is the case.

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Mikhail Goykhman. 2015-01-29. On entanglement entropy in 't Hooft model. https://doi.org/10.1103/physrevd.92.025048

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