MESON BOUND-STATES IN AN SU(N) SCALAR MODEL

A four-dimensional SU(N) model of scalar "quarks", "antiquarks", and "gluons" whose large-N structure closely resembles that of two-dimensional planar QCD is presented. The dominant self-energy and ladder diagrams in this model are summed to leading order in 1/N. The Schwinger-Dyson equation for the "quark" propagator is solved for the propagator's spectral representation. The mass spectrum for "quark-antiquark" mesons is then numerically calculated from the Bethe-Salpeter equation. The large-N results are compared with bound state predictions from lowest-order perturbation theory and the Schrodinger equation in the nonrelativistic limit. The nonperturbative and perturbative spectra are found to differ significantly in the strongly interacting sector of the model.