PHASE-DIAGRAM OF THE N = 2 KAZAKOV-MIGDAL MODEL

We have determined the phase diagram of the simplest version of a lattice model recently introduced by Kazakov and Migdal. Denoting by m0 and lambda the mass and the coupling of the scalar field in the model, we find a line of first-order phase transitions in the (m0,lambda) plane ending in a critical point where lambda is nonzero. Kazakov and Migdal speculate that their model of scalar field theory could induce QCD. Our work indicates that there is no continuum limit except at the critical end point. Whether or not a non-trivial continuum limit exists there requires a careful study of the renormalization-group properties of the model.