New Aspects on a Seesaw Mass Matrix Model
نویسنده
چکیده
Recent development of the universal seesaw mass matrix model is reviewed. The model was proposed in order to explain why quark and lepton masses are so small compared with the electroweak scale ΛL = 〈φL〉 = 174 GeV. However, the recently observed top-quark mass mt ≃ 180 GeV seems to make an objection against the seesaw mass picture. For this problem, it has recently pointed out that the seesaw mass matrix model is rather favorable to the fact mt ∼ ΛL if we consider the model with detMF = 0 for up-quark sector, where MF is a 3× 3 mass matrix of hypothetical heavy fermions F . The model can give a natural explanation why only top-quark acquire the mass of the order of ΛL. The model with detMU = 0 offers abundant new physics to us (e.g., the fourth up-quark t′, FCNC, and so on).
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