Search for composite models with family gauge symmetries

Abstract

We have analyzed a class of three-preon models based on a strategy expected to lead to family gauge symmetry SU^F(n) and found that, in order to obey the assumption of asymptotic freedom and infrared confinement for the hypercolor group SU_H(N), 't Hooft anomaly consistency conditions, especially the requirement of dynamical generation of quark-lepton masses by means of color condensates of exotic fermions, the only possible model is the three-fermion model with the hypercolor group SU_H(4) and the family gauge group SU^F(2), which was proposed in ref. [7]. All the models considered which contain scalar-preons are excluded from being realistic models unless some new mechanism of quark-lepton mass generation is worked out.