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arXiv · 2608.03366

Notes on phase structure and non-vanishing $\beta$ functions of one-unitary matrix model

Hiroshi Itoyama·Reiji Yoshioka
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Abstract

Unitary matrix models, among other things, play an important role in representing the irregular conformal block and hence LEEA of some asymptotically free susy gauge theories. Here, we develop a method of how to determine the qualitative structure of phase diagram by the deformation of classical potential, and illustrate this by the examples that contain term up to $\cos n\alpha$, $n \leq 3$. We point out that a set of $\beta$ functions on critical ``lines" is nowhere a vanishing vector. This generalizes the $n =1$ GWW case and tells us the third order (rather than second order) phase transition in conformity with the range of values for the susceptibility exponent.

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Hiroshi Itoyama, Reiji Yoshioka. 2026-08-04. Notes on phase structure and non-vanishing $\beta$ functions of one-unitary matrix model. https://arxiv.org/abs/2608.03366

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