Neutrino Mass Models: circa 2008

TL;DR

This paper reviews recent theoretical models for neutrino masses and mixing, focusing on finite group symmetries and specific models based on SU(5) and U(1)_F symmetries, highlighting their features and implications.

Contribution

It introduces new models based on SU(5) and U(1)_F symmetries that explain neutrino mixing and address issues like proton decay and the seesaw scale.

Findings

Model achieves tri-bimaximal neutrino mixing

Seesaw scale can be as low as a TeV

U(1)_F symmetry suppresses proton decay

Abstract

We review recent developments in theoretical models for neutrino masses and mixing. Emphases are given to models based on finite group family symmetries. In particular, we describe one recent model based on SU(5), in which both the tri-bimaximal neutrino mixing and realistic CKM matrix are generated. We also discuss two models based on a non-anomalous U(1)_F family symmetry in which the gauge anomalies are cancelled due to the presence of the right-handed neutrinos. In one of these models, the seesaw scale can be as low as a TeV; in the other model, which is based on SUSY SU(5), the U(1)_F symmetry forbids Higgs-mediated proton decays.