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Mean-field expansion for spin models with medium-range interactions

A. Pelissetto·P. Rossi·E. Vicari
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Abstract

We study the critical crossover between the Gaussian and the Wilson-Fisher fixed point for general O(N)-invariant spin models with medium-range interactions. We perform a systematic expansion around the mean-field solution, obtaining the universal crossover curves and their leading corrections. In particular we show that, in three dimensions, the leading correction scales as $R^{-3}, R$ being the range of the interactions. We compare our results with the existing numerical ones obtained by Monte Carlo simulations and present a critical discussion of other approaches.

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A. Pelissetto, P. Rossi, E. Vicari. 1999-03-29. Mean-field expansion for spin models with medium-range interactions. https://doi.org/10.1016/s0550-3213(99)00311-9

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