DYNAMICAL SYMMETRY-BREAKING AND THE TOP-QUARK MASS

Dynamical symmetry breaking by fermion condensates is assumed to be the source of gauge-boson masses in the SU(3)C×SU(2)L×U(1) model. For the minimal case of tt» condensation alone, the predicted mt ranges from about 98 to 450 GeV as the scale of "new physics," responsible for mt, goes from to 1 TeV. The lighter values, mt200 GeV, all correspond to "great desert" scenarios with mPlanck2×1019 GeV. Including a fourth generation of fermion condensates can lower mt. In the case of maximal t-t mixing, we find mtmt(32)mb with mt ranging from about 90 to 250 GeV, and mt140 GeV for 1015-1019 GeV. For smaller mixing, mt is lowered and mb approaches mt200. We speculate as to how, using strong-coupling unitarity conditions, one might have GeV with far below mPlanck. Phenomenological constraints and consequences are also discussed. © 1990 The American Physical Society.