High-accuracy critical exponents of O(N) hierarchical sigma models

J. J. Godina; L. Li; Y. Meurice; M. B. Oktay

doi:10.1063/1.2359255

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arXiv · hep-th/0511194

High-accuracy critical exponents of O(N) hierarchical sigma models

J. J. Godina·L. Li·Y. Meurice·M. B. Oktay

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Abstract

We perform high-accuracy calculations of the critical exponent gamma and its subleading exponent for the 3D O(N) Dyson's hierarchical model, for N up to 20. We calculate the critical temperatures for the nonlinear sigma model measure. We discuss the possibility of extracting the first coefficients of the 1/N expansion from our numerical data. We show that the leading and subleading exponents agreewith Polchinski equation and the equivalent Litim equation, in the local potential approximation, with at least 4 significant digits.

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J. J. Godina, L. Li, Y. Meurice, M. B. Oktay. 2005-11-19. High-accuracy critical exponents of O(N) hierarchical sigma models. https://doi.org/10.1063/1.2359255

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