Effective Lagrangian approach to the fermion mass problem

Abstract

An effective theory is proposed, combining the standard gauge group SU(3)c 8 SU(2)L 8 U(l)Y with a horizontal discrete symmetry. By assigning appropriate charges under this discrete symmetry to the various fermion fields and to (at least) two Higgs doublets, the broad spread of the fermion mass and mixing angle spectrum can be explained as a result of suppressed, nonrenormalizable terms. A particular model is constructed which achieves the above while simultaneously suppressing neutral Higgs-induced flavor-changing processes.PACS number(s): 12.15.Ff, 12.15.Hh