LEPTON MASS HIERARCHY AND NEUTRINO OSCILLATIONS

Starting from the symmetry of lepton flavor democracy, we propose and discuss a simple pattern for the mass generation and flavor mixing of the charged leptons and neutrinos. The three neutrino masses are nearl y degenerate, and the flavor mixing angles can be calculated, The obse rved deficit of solar and atmospheric neutrinos can be interpreted as a consequence of the near degeneracy and large oscillations of nu(e), nu(mu) and nu(tau) in the vacuum. Our ansatz can also accommodate the cosmological requirement for hot dark matter and the current data on n eutrinoless beta beta-decay.