Three-loop critical exponents, amplitude functions, and amplitude ratios from variational perturbation theory

H. Kleinert; B. Van den Bossche

doi:10.1103/physreve.63.056113

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Three-loop critical exponents, amplitude functions, and amplitude ratios from variational perturbation theory

H. Kleinert·B. Van den Bossche

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Abstract

We use variational perturbation theory to calculate various universal amplitude ratios above and below T_c in minimally subtracted phi^4-theory with N components in three dimensions. In order to best exhibit the method as a powerful alternative to Borel resummation techniques, we consider only to two- and three-loops expressions where our results are analytic expressions. For the critical exponents, we also extend existing analytic expressions for two loops to three loops.

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H. Kleinert, B. Van den Bossche. 2000-11-20. Three-loop critical exponents, amplitude functions, and amplitude ratios from variational perturbation theory. https://doi.org/10.1103/physreve.63.056113

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