A model for trimaximal lepton mixing

TL;DR

This paper introduces a model for lepton mixing that enforces trimaximal mixing using softly broken discrete symmetries, notably Delta(27), without requiring vacuum alignment.

Contribution

It presents a novel model for lepton mixing based on discrete symmetries that achieves trimaximal mixing without vacuum alignment.

Findings

Achieves trimaximal lepton mixing with a two-parameter matrix

Uses softly broken discrete symmetries, specifically Delta(27)

Does not require vacuum alignment in the model

Abstract

We consider trimaximal lepton mixing, defined by |U_{alpha 2}|^2 = 1/3 for all alpha = e, mu, tau. This corresponds to a two-parameter lepton mixing matrix U. We present a model for the lepton sector in which trimaximal mixing is enforced by softly broken discrete symmetries; one version of the model is based on the group Delta(27). A salient feature of our model is that no vacuum alignment is required.