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Towards a Direct Method for the Analyticity of the Pressure for Certain Classical Unbounded Spin Systems

Assane Lo
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Abstract

The aim of this paper is to study direct methods for the analyticity of the pressure for certain classical unbounded spin models. We provide a representation in terms of the Witten Laplacian on one-forms of the nth-derivative of the pressure as function of some order parameter t . The technique involves the formula for the covariance of two functions introduced by B. Helffer and J. Sjostrand.

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Assane Lo. 2007-03-24. Towards a Direct Method for the Analyticity of the Pressure for Certain Classical Unbounded Spin Systems. https://arxiv.org/abs/math-ph/0611004

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