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arXiv · 1010.0912

Asymptotic safety and the gauged SU(N) nonlinear sigma-model

M. Fabbrichesi·R. Percacci·A. Tonero·O. Zanusso
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Abstract

We study the beta functions of the leading, two-derivative terms of the left-gauged SU(N) nonlinear sigma-model in d dimensions. In d>2, we find the usual Gaussian ultraviolet fixed point for the gauge coupling and an attractive non-Gaussian fixed point for the Goldstone boson coupling. The position of the latter fixed point controls the chiral expansion, unitarity and the strength of the tree-level Goldstone boson scattering amplitudes. Attention is paid to the gauge- and scheme-dependence of the results.

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M. Fabbrichesi, R. Percacci, A. Tonero, O. Zanusso. 2010-10-05. Asymptotic safety and the gauged SU(N) nonlinear sigma-model. https://doi.org/10.1103/physrevd.83.025016

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