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A Road to the Standard Grand Unified Theory

Nobuhiro Maekawa
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Abstract

In this talk, we propose a GUT scenario in which doublet-triplet splitting is naturally realized in SO(10) unification using the Dimopoulos-Wilczek mechanism and the realistic mass matrices of quarks and leptons are obtained in a simple way. For the neutrino sector, bi-maximal neutrino mixing angles are realized. Moreover, the generic interaction is allowed, namely, all the terms which are allowed by the symmetry are included in the scenario. Therefore, once we fix the integer number charges of the anomalous U(1)_A symmetry, which plays an essential role in the scenario, all the scales, GUT breaking scale, mass scales of superheavy particles, are determined. The scenario can be extended into E_6 unification, in which a condition for suppression of flavor changing neutral current (FCNC) is automatically satisfied.

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Nobuhiro Maekawa. 2001-10-22. A Road to the Standard Grand Unified Theory. https://arxiv.org/abs/hep-ph/0110276

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