Lepton Sector Phases and Their Roles in Flavor and Generalized CP Symmetries

TL;DR

This paper investigates how unphysical phases in the lepton sector influence the mathematical structure of flavor and generalized CP symmetries, impacting model building in neutrino physics.

Contribution

It analyzes the role of unphysical lepton phases in the group properties of flavor and CP symmetries for Majorana neutrinos, providing insights for discrete symmetry models.

Findings

Unphysical phases alter the group structure of symmetry elements.

Differences between charged lepton and neutrino sectors are clarified.

Implications for constructing flavor models with discrete symmetries are discussed.

Abstract

We study the effects of considering nontrivial unphysical lepton sector phases on the group theoretical properties of the flavor and generalized CP symmetry elements in the case where there are three light, distinct Majorana neutrino species. We highlight the similarities and differences between the charged lepton and neutrino sectors and further elucidate the group properties of the flavor and generalized CP symmetry elements. We show how the inclusion of these leptonic phases affects the bottom-up constructions of these symmetry elements and discuss the implications for top-down model building based on discrete symmetry groups.