2002/04/30 by Joaquim I. Silva-Marcos, Joaquim I Silva-Marcos · 1 citation
Physics and Astronomy · #Discrete symmetry #Fourth generation #Lepton #Lepton number #Mass generation #Mixing (physics) #Neutrino #Neutrino Physics Research #Particle physics theoretical and experimental studies #Quantum and Classical Electrodynamics #Standard Model (mathematical formulation) #Symmetry (geometry) #hep-ph
paper · pdf · doi:10.1088/1126-6708/2002/12/036
published as JHEP 0212:036,2002 · 6 pages, ReVTeX, no figures
arxiv created 2002/06/19 · openalex publication_date 2002/12/10 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We show that large leptonic mixing occurs most naturally in the framework of the Sandard Model just by adding a fourth generation. One can then construct a small Z4 discrete symmetry, instead of the large S4L× S4R, which requires that the neutrino as well as the charged lepton mass matrices be proportional to a 4× 4 democratic mass matrix, where all entries are equal to unity. Without considering the see-saw mechanism, or other more elaborate extensions of the SM, and contrary to the case with only 3 generations, large leptonic mixing is obtained when the symmetry is broken.