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arXiv · hep-th/9512135

Light-Front QCD(1+1) Coupled to Chiral Adjoint Fermions

Stephen S. Pinsky·David G. Robertson
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Abstract

We consider SU(N) gauge theory in 1+1 dimensions coupled to chiral fermions in the adjoint representation of the gauge group. With all fields in the adjoint representation the gauge group is actually SU(N)/Z_N, which possesses nontrivial topology. In particular, there are N distinct topological sectors and the physical vacuum state has a structure analogous to a θvacuum. We show how this feature is realized in light-front quantization for the case N=2, using discretization as an infrared regulator. In the discretized form of the theory the nontrivial vacuum structure is associated with the zero momentum mode of the gauge field A^+. We find exact expressions for the degenerate vacuum states and the analog of the θvacuum. The model also possess a condensate which we calculate. We discuss the difference between this chiral light-front theory and the theories that have previously been considered in the equal-time approach.

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Stephen S. Pinsky, David G. Robertson. 1995-12-25. Light-Front QCD(1+1) Coupled to Chiral Adjoint Fermions. https://doi.org/10.1016/0370-2693(96)00252-3

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