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On the convergence of Kikuchi's natural iteration method

Marco Pretti
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Abstract

In this article we investigate on the convergence of the natural iteration method, a numerical procedure widely employed in the statistical mechanics of lattice systems to minimize Kikuchi's cluster variational free energies. We discuss a sufficient condition for the convergence, based on the coefficients of the cluster entropy expansion, depending on the lattice geometry. We also show that such a condition is satisfied for many lattices usually studied in applications. Finally, we consider a recently proposed general method for the minimization of non convex functionals, showing that the natural iteration method turns out as a particular case of that method.

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Marco Pretti. 2004-04-27. On the convergence of Kikuchi's natural iteration method. https://doi.org/10.1007/s10955-005-4426-x

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