E6 unification and anomalous U(1) symmetry

by Nobuhiro Maekawa (Kyoto University)

Thursday 22 Jul 2004, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

Though the success of the gauge coupling unification suggests that SUSY GUT is promising, it may not be known that it was difficult to give a natural explanation for the success in 4 dimensional SUSY GUT and to keep the stability of the nucleon. In this seminar, it is shown that GUT with the anomalous U(1) symmetry (or U(1) with Fayet-Illiopoulos D-term) gives a new explanation for this success and solves almost all problems in the scenario of SUSY GUT under the generic interactions (including non-renormalizable interactions), for example, the doublet-triplet splitting problem, stability of proton (via dimension 5 operators), unrealistic GUT relations between Yukawa couplings. Because all the interactions that are allowed by the symmetry are introduced, the theory can be defined only by the symmetry except the O(1) coefficients.