We discuss systematically the fermion mass and mixing matrices in a generic field-theoretical flipped SU(5) model, with particular applications to neutrino and baryon number-changing physics. We demonstrate that the different quark flavour branching ratios in proton decay are related to the Cabibbo-Kobayashi-Maskawa angles, whereas the lepton flavour branching ratios are undetermined. The light neutrino mixing angles observable via oscillation effects are related to the heavy conjugate (right-handed) neutrino mass matrix, which also play a key role in cosmological baryogenesis. The ratios of neutrino and charged lepton decay modes in baryon decay may also be related to neutrino oscillation parameters. Plausible Ansätze for the generation structure of coupling matrices motivate additional relations between physical observables, and yield a satisfactory baryon asymmetry.
Bibliographical noteFunding Information:
The work of J.L.L. has been supported by an SSC Fellowship. The work of D.V.N. was supported in part by DOE grant DE-FG05-91-ER-40633 and by a grant from Conoco Inc. The work of K.A.O. was supported in part by DOE grant DE-AC02-83ER-40105, and by a Presidential Young Investigator Award. J.L.L. would like to thank the CERN Theory Division for its kind hospitality while part of this work was carried out.