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A Model for Fermion Mass Hierarchies and Mixings

P. Ramond
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Abstract

We present a model which contains three Abelian symmetries beyond the standard model. One is anomalous {\it \` a la} Green-Schwarz, and family-independent; the other two are family symmetries. All are broken at a large scale by stringy effects. The model is predictive in the neutrino sector: large mixing between $ν_μ-ν_τ$, and {\cal O}$(λ^3)$ $ν_e-ν_μ$ mixings. Its natural cut-off is the gauge unification scale, orders of magnitude below the perturbative string cut-off.

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P. Ramond. 1998-08-31. A Model for Fermion Mass Hierarchies and Mixings. https://arxiv.org/abs/hep-ph/9808489

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