Neutrino Properties from E_6 x SO(3) x Z(2)

TL;DR

This paper presents a grand unified model combining E_6 with SO(3) x Z(2) to explain fermion masses, mixings, and CP violation, predicting an inverted neutrino hierarchy and TeV-scale right-handed neutrinos.

Contribution

It introduces a novel grand unification framework linking neutrino properties with fermion mass hierarchies using scalar flavons.

Findings

Reproduces all known fermion properties with few parameters

Predicts an inverted neutrino mass hierarchy

Suggests TeV-scale masses for two right-handed neutrinos

Abstract

The group E_6 for grand unification is combined with the generation symmetry group SO(3) x Z(2). The coupling matrices in the Yukawa interaction are identified with the vacuum expectation values of scalar flavons. The symmetric part of this 3x3 coupling matrix can be identified with the known up-quark hierarchy. The antisymmetric part is responsible for fermion mixings and CP violation. Numerical fits with only few parameters reproduce quantitatively all known fermion properties. The model predicts an inverted neutrino hierarchy, CP violation properties as well as the 0v2beta decay parameter. It also predicts that the masses of the two lightest of six `right handed' neutrinos lie in the low TeV region.