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arXiv · hep-th/9805155

The spectrum of multi-flavor QCD_2 and the non-Abelian Schwinger equation

A. Armoni·Y. Frishman·J. Sonnenschein·U. Trittmann
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Abstract

Massless $QCD_2$ is dominated by classical configurations in the large $N_f$ limit. We use this observation to study the theory by finding solutions to equations of motion, which are the non-Abelian generalization of the Schwinger equation. We find that the spectrum consists of massive mesons with $M^2={e^2 N_f\over 2π}$ which correspond to Abelian solutions. We generalize previously discovered non-Abelian solutions and discuss their interpretation. We prove a no-go theorem ruling out the existence of soliton solutions. Thus the semi-classical approximation shows no baryons in the case of massless quarks, a result derived before in the strong-coupling limit only.

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A. Armoni, Y. Frishman, J. Sonnenschein, U. Trittmann. 1998-05-24. The spectrum of multi-flavor QCD_2 and the non-Abelian Schwinger equation. https://doi.org/10.1016/s0550-3213(98)00664-6

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