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Communications in Theoretical Physics

Convergence of the Variational Cumulant Expansion

Ying Chen, Zhu Yunlun

Published Sep 15, 1997• 2 citations
Publisher

Abstract

In this article we discuss the convergence of the variational cumulant expansion (VCE) in the Ising model and lattice model. We find that in critical region VCE results do not converge so quickly as elsewhere and the analyticity of thermo-dynamical functions and the strong correlation in the critical region are responsible for this fact.
DOI
10.1088/0253-6102/28/2/241

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