Mass and Flavor Mixing Schemes of Quarks and Leptons

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass generation could be built, are emphasized. A variety of schemes of quark mass matrices at low and superhigh energy scales are described, and their consequences on flavor mixing and CP violation are discussed. Instructive patterns of lepton mass matrices, which can naturally lead to large flavor mixing angles, are explored to interpret current data on atmospheric and solar neutrino oscillations. We expect that B-meson factories and long-baseline neutrino experiments will soon shed more light on the dynamics of fermion masses, flavor mixing and CP violation. Invited Article to appear in Vol. 45 of Prog. Part. Nucl. Phys. Elsevier Science, The Netherlands (2000) ‘E-mail: xingOhep.physik.uni-muenchen.de 0146-6410/00/S see front matter