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arXiv · 2010.02950

Phases of unitary matrix models and lattice QCD2

Jorge G. Russo
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Abstract

We investigate the different large $N$ phases of a generalized Gross-Witten-Wadia $U(N)$ matrix model. The deformation mimics the one-loop determinant of fermion matter with a particular coupling to gauge fields. In one version of the model, the GWW phase transition is smoothed out and it becomes a crossover. In another version, the phase transition occurs along a critical line in the two-dimensional parameter space spanned by the 't~Hooft coupling $\lambda$ and the Veneziano parameter $\tau$. We compute the expectation value of Wilson loops in both phases, showing that the transition is third-order. A calculation of the $\beta $ function shows the existence of an IR stable fixed point.

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Jorge G. Russo. 2020-10-06. Phases of unitary matrix models and lattice QCD2. https://doi.org/10.1103/physrevd.102.105019

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