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arXiv · 1412.2534

Some Properties of Correlations of Quantum Lattice Systems in Thermal Equilibrium

Juerg Froehlich·Daniel Ueltschi
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Abstract

Simple proofs of uniqueness of the thermodynamic limit of KMS states and of the decay of equilibrium correlations are presented for a large class of quantum lattice systems at high temperatures. New quantum correlation inequalities for general Heisenberg models are described. Finally, a simplified derivation of a general result on power-law decay of correlations in 2D quantum lattice systems with continuous symmetries is given, extending results of Mc Bryan and Spencer for the 2D classical XY model.

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Juerg Froehlich, Daniel Ueltschi. 2015-05-27. Some Properties of Correlations of Quantum Lattice Systems in Thermal Equilibrium. https://doi.org/10.1063/1.4921305

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