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arXiv · hep-lat/9307014

Two dimensional SU(N) x SU(N) chiral models on the lattice

Paolo Rossi·Ettore Vicari
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Abstract

Lattice $SU(N)\times SU(N)$ chiral models are analyzed by strong and weak coupling expansions and by numerical simulations. $12^{th}$ order strong coupling series for the free and internal energy are obtained for all $N\geq 6$. Three loop contributions to the internal energy and to the lattice $β$-function are evaluated for all $N$ and non-universal corrections to the asymptotic $Λ$ parameter are computed in the ``temperature'' and the ``energy'' scheme. Numerical simulations confirm a faster approach to asymptopia of the energy scheme. A phenomenological correlation between the peak in the specific heat and the dip of the $β$-function is observed. Tests of scaling are performed for various physical quantities, finding substantial scaling at $ξ\gtrsim 2$. In particular, at $N=6$ three different mass ratios are determined numerically and found in agreement, within statistical errors of about 1\%, with the theoretical predictions from the exact S-matrix theory.

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Paolo Rossi, Ettore Vicari. 1993-09-08. Two dimensional SU(N) x SU(N) chiral models on the lattice. https://doi.org/10.1103/physrevd.49.1621%2010.1103%2Fphysrevd.55.1698

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