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Is the mean-field approximation so bad? A simple generalization yelding realistic critical indices for 3D Ising-class systems

A. N. Rubtsov
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Abstract

Modification of the renormalization-group approach, invoking Stratonovich transformation at each step, is proposed to describe phase transitions in 3D Ising-class systems. The proposed method is closely related to the mean-field approximation. The low-order scheme works well for a wide thermal range, is consistent with a scaling hypothesis and predicts very reasonable values of critical indices.

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A. N. Rubtsov. 2002-01-10. Is the mean-field approximation so bad? A simple generalization yelding realistic critical indices for 3D Ising-class systems. https://doi.org/10.1103/physrevb.66.052107

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