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arXiv · 1604.02117

String completion of an $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ electroweak model

Abstract

The extended electroweak $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ symmetry framework "explaining" the number of fermion families is revisited. While $331$-based schemes can not easily be unified within the conventional field theory sense, we show how to do it within an approach based on D-branes and (un)oriented open strings, on Calabi-Yau singularities. We show how the theory can be UV-completed in a quiver setup, free of gauge and string anomalies. Lepton and baryon numbers are perturbatively conserved, so neutrinos are Dirac-type, and their lightness results from a novel TeV scale seesaw mechanism. Dynamical violation of baryon number by exotic instantons could induce neutron-antineutron oscillations, with proton decay and other dangerous R-parity violating processes strictly forbidden.

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BibTeXRIS

Andrea Addazi, J. W. F. Valle, C. A. Vaquera-Araujo. 2016-09-06. String completion of an $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ electroweak model. https://doi.org/10.1016/j.physletb.2016.06.015

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