A grand unified technicolor theory and the fermion masses of the first and third generation
نویسنده
چکیده
We build a grand unified theory based on the SU(9) group. The theory contains the standard model and a SU(4)TC technicolor group. The replication of families is introduced through a horizontal (or family) SU(3)H symmetry. Assuming a Fritzsh texture for the fermion mass matrix and with only one hypothesis about the dynamics of the strongly interacting sector we obtain a fermionic mass spectrum with a reasonable value for the top quark mass as well as for the fermion masses of the first generation. The b quark and τ lepton masses are overestimated and, as a consequence, the s quark and μ lepton masses are roughly a factor four larger than the experimental values. Within this model the origin of the mass scales of the first and third fermionic generation is naturally explained. The model has no flavor changing neutral currents at unwanted levels. We discuss the masses of pseudo-goldstone bosons and possible modifications in the model that could promote a larger splitting between the masses of the third fermionic generation, bringing also the masses of the second generation to a reasonable value.
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تاریخ انتشار 2003