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arXiv · hep-lat/9209026

Bose Condensation and $Z_N$ Symmetry Breaking in the Mixed Model of Induced QCD

A. A. Migdal
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Abstract

The mixed model of the large $ N $ induced QCD, with $ N_f \ll N $ flavors of heavy fermions in fundamental representation, is solved in the local limit. The $ Z_N$ symmetry is broken spontaneously in the large $ N $ limit, evading the Elitzur "no-go" theorem. As a result of this symmetry breaking, there is the Bose condensate of the eigenvalues of the scalar field, proportional to $ \frac{N_f}{N} $. This condensate leads to the mass unit, which goes to zero as fractional power of $ \frac{N_f}{N} $, thus defining the new kind of the local limit of this lattice theory. There is a strong coupling region below this mass scale, which revives the hopes of induction of realistic QCD.

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A. A. Migdal. 1992-09-29. Bose Condensation and $Z_N$ Symmetry Breaking in the Mixed Model of Induced QCD. https://doi.org/10.1142/s021773239300026x

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