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Pseudo-epsilon expansion and the two-dimensional Ising model

A. I. Sokolov
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Abstract

Starting from the five-loop renormalization-group expansions for the two-dimensional Euclidean scalar ϕ^4 field theory (field-theoretical version of two-dimensional Ising model), pseudo-εexpansions for the Wilson fixed point coordinate g*, critical exponents, and the sextic effective coupling constant g_6 are obtained. Pseudo-εexpansions for g*, inverse susceptibility exponent γ, and g_6 are found to possess a remarkable property - higher-order terms in these expansions turn out to be so small that accurate enough numerical estimates can be obtained using simple Pade approximants, i. e. without addressing resummation procedures based upon the Borel transformation.

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A. I. Sokolov. 2005-10-05. Pseudo-epsilon expansion and the two-dimensional Ising model. https://doi.org/10.1134/1.2131160

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