GENERATION PROBLEM AND SO(14) GRAND UNIFIED THEORIES
- Received Date: 1980-08-13
- Accepted Date: 1900-01-01
- Available Online: 1981-12-05
Abstract: Three models of grand unified theory based on SO(14) gauge group are proposed. They can accommodate four generations of odinary fermions. Model A, where the charged weak currents of the fermions in the first and second generations are V-A and that of the fermions in the third and fourth generations are V + A, is a natural model from the point of view of structure of SO(14). In model B, we obtain the nice value of Weinberg angle: sin2θw=0.225 and the masses of W± and the ordinary Z° are a factor 1.7 larger than those in SU(5) standard model. Model B predicts another neutral vector boson which couples with the fermions in the first two generations like a heavy photon with the mass of the order of 100 GeV. The coupling of τ—νr. in model B is V—A. All light fermions in model C have left-handed charged weak current. All these models can accommodate mass relations: mα·mμ~md·mτ,mμ~3ms,mr~mb andgive the first Cabibbo angle sinθ1= √md/ms.