Effects of quark family nonuniversality in SU(3)_c X SU(4)_L X U(1)_x models

Jorge L. Nisperuza, Luis A. Sanchez

Flavour changing neutral currents arise in the $SU(3{)}_c\otimes SU(4{)}_L\otimes U(1{)}_X$ extension of the standard model because anomaly cancellation among the fermion families requir…