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On the evaluation of universal non-perturbative constants in O(N) sigma models

M. Campostrini·A. Pelissetto·P. Rossi·E. Vicari
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Abstract

We investigate the relation between on-shell and zero-momentum non-perturbative quantities entering the parametrization of the two-point Green's function of two-dimensional non-linear O(N) sigma models. We present accurate estimates of ratios of mass-scales and renormalization constants, obtained by an analysis of the strong-coupling expansion of the two-point Green's function. These ratios allow to connect exact known on-shell results with typical zero-momentum lattice evaluations. Our results are supported by the 1/N-expansion.

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M. Campostrini, A. Pelissetto, P. Rossi, E. Vicari. 1997-02-10. On the evaluation of universal non-perturbative constants in O(N) sigma models. https://doi.org/10.1016/s0370-2693(97)00456-5

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