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arXiv · 1011.2664

A solution of the Gross-Witten matrix model by nonlinear random processes

P. V. Buividovich
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Abstract

We illustrate the stochastic method for solving the Schwinger-Dyson equations in large-N quantum field theories described in ArXiv:1009.4033 on the example of the Gross-Witten unitary matrix model. In the strong-coupling limit, this method can be applied directly, while in the weak-coupling limit we change the variables from compact to noncompact ones in order to cast the Schwinger-Dyson equations in the stochastic form. This leads to a new action with an infinite number of higher-order interaction terms. Nevertheless, such an action can be efficiently handled. This suggests the way to apply the method of ArXiv:1009.4033 to field theories with U(N) field variables as well as to effective field theories in the large-N limit.

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P. V. Buividovich. 2010-11-11. A solution of the Gross-Witten matrix model by nonlinear random processes. https://doi.org/10.1063/1.3574987

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