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arXiv · hep-th/9709195

An Approximate Large $N$ Method for Lattice Chiral Models

Stuart Samuel
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Abstract

An approximation is used that permits one to explicitly solve the two-point Schwinger-Dyson equations of the U(N) lattice chiral models. The approximate solution correctly predicts a phase transition for dimensions $d$ greater than two. For $d \le 2 $, the system is in a single disordered phase with a mass gap. The method reproduces known $N=\infty$ results well for $d=1$. For $d=2$, there is a moderate difference with $N=\infty$ results only in the intermediate coupling constant region.

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Stuart Samuel. 1997-09-26. An Approximate Large $N$ Method for Lattice Chiral Models. https://doi.org/10.1103/physrevd.56.1470

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