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Bounds on Correlation Functions of Quantum Rotators

Oscar Bolina·J. Rodrigo Parreira
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Abstract

We derive a McBryan-Spencer bound to the correlation function of a one-dimensional array of quantum rotators in the Villain approximation of the cosine interaction. We obtain the partition function of the system in the gas representation and establish a lower bound on the external charge correlation function. We also discuss the possible existence of a Kosterlitz-Thouless phase for the quantum rotator in the Villain approximation.

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Oscar Bolina, J. Rodrigo Parreira. 1999-05-06. Bounds on Correlation Functions of Quantum Rotators. https://arxiv.org/abs/math-ph/9905004

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