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Loop expansion around the Bethe-Peierls approximation for lattice models

Giorgio Parisi·Frantisek Slanina
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Abstract

We develop an effective field theory for lattice models, in which the only non-vanishing diagrams exactly reproduce the topology of the lattice. The Bethe-Peierls approximation appears naturally as the saddle point approximation. The corrections to the saddle-point result can be obtained systematically. We calculate the lowest loop corrections for magnetisation and correlation function.

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Giorgio Parisi, Frantisek Slanina. 2005-12-21. Loop expansion around the Bethe-Peierls approximation for lattice models. https://doi.org/10.1088/1742-5468%2F2006%2F02%2Fl02003

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