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arXiv · 2002.04253

Gibbs variational formula for thermal equilibrium states in terms of quantum relative entropy density

Hajime Moriya
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Abstract

We prove the Gibbs variational formula in terms of quantum relative entropy density that characterizes translation invariant thermal equilibrium states in quantum lattice systems. It is a natural quantum extension of the similar statement established by F\"ollmer for classical systems. In this work we advocate the viewpoint: Avoid the unique-phase assumption if it is not essential.

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Hajime Moriya. 2020-02-11. Gibbs variational formula for thermal equilibrium states in terms of quantum relative entropy density. https://arxiv.org/abs/2002.04253

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