UNIVERSITY IN 2-DIMENSIONAL GAUGE-THEORY

We discuss two-dimensional Yang-Mills theories with massless fermions in arbitrary representations of a gauge group G, It is shown that the physics (spectrum and interactions) of the massive states in such mode ls is independent of the detailed structure of the model, and only dep ends on the gauge group G and an integer k measuring the total anomaly . The massless physics, which does depend on the details of the model, decouples (almost) completely from that of the massive one. As an exa mple, we discuss the equivalence of QCD(2) coupled to fermions in the adjoint, and fundamental representations.