Dynamical-symmetry-breaking solution to the problem of leptons

We propose a fully dynamical ''moose'' model with lepton condensates. A fourth family is introduced so that the scale of new physics Λ may be in the TeV range, and hence there is no fine tuning. Flavor-changing neutral currents are suppressed by a Glashow-Iliopoulos-Maiani mechanism. The fourth-family neutrinos have a Dirac mass ∼Λ, while the first three families of neutrinos are massless. The model involves several gauge groups becoming strong simultaneously, and in order for the model to give a desirable phenomenology we have to make a number of dynamical assumptions as discussed in the text