STRING EQUATIONS FROM UNITARY MATRIX MODELS

Abstract

We investigate unitary matrix models in the scaling limit using the method of orthogonal polynomials on the unit circle. We show that, f or a certain choice of coupling constants, string equations belong to the same univesality class as equations obtained from Hermitian matrix models. In addition, we show how a new class of string equations emerges as a consequence of the compactness of the unitary groups.