Universal mixing of leptons in a gauge theory of weak interactions

In the framework of the SU (2)/sub L/ x U (1) gauge theory we formulate a model of universal lepton mixing, together with a rule for the determination of the mixing angles in terms of the masses of the charged leptons. A comparison with experimental data leads to the conclusion that above the tau lepton there must exist a more massive tau' lepton, the mass of which is the only unknown parameter determining the cross sections for neutrino production and decay of all charged leptons. Under this condition the model agrees no worse than the sequenton model with all known facts of lepton physics, but also makes new predictions relative to the possibility of tau-lepton production in neutrino experiments, predictions which are discussed in the paper.