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arXiv · 1810.10642

Some Results On Relative Entropy in Quantum Field Theory

Feng Xu
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Abstract

We prove that the mutual information for vacuum state as defined by Araki is finite for quantum field theory of free fermions on a Minkowski spacetime of any dimension. In the case of two dimensional chiral conformal field theory (CFT) we use our previous results for the free fermions to show that for a large class of chiral CFT the mutual information is finite. We also provide a direct relation between relative entropy and the index of a representation of conformal net.

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Feng Xu. 2018-10-24. Some Results On Relative Entropy in Quantum Field Theory. https://doi.org/10.1007/s00220-019-03367-x

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