2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/184085After some general remarks about SU_L(4) electroweak unification, the model is extended to SU_L(4)xU_X(1) to accomodate fractionally charged quarks. The unification scale is expected to be in TeV region. A right-handed Majorana neutrino along with known lepton are put in the fundamental representation of SU_L(4) with Y_X=0. The see-saw mechanism for neutrino masses and flavor mixing in neutrino sector is a natural feature of the model. The lepton number violating processes can occure through dilepton gauge bosons contained in the model.RevTeX, 9 pages, no figure: replaced with revised versionHigh Energy Physics - Phenomenologytext