Neutrino mass generation from the perspective of presymmetry

TL;DR

This paper explores how presymmetry, a global $U(1)_{B-L}$ symmetry, influences neutrino mass generation mechanisms, highlighting the roles of Dirac, Majorana, and pseudo-Dirac neutrinos within the Standard Model framework.

Contribution

It provides a novel perspective on neutrino masses by analyzing high-scale and low-scale seesaw mechanisms through the lens of presymmetry and fractional charge normalization.

Findings

Pseudo-Dirac neutrinos include sterile neutrinos with presymmetry signatures.

Heavy neutrino masses favor low-scale linear seesaw over inverse seesaw.

The $U(1)_{B-L}$ symmetry is interpreted as a residual presymmetry in the SM.

Abstract

The Standard Model (SM) with one right-handed neutrino per generation is revisited with presymmetry being the global $U(1)_{B-L}$ symmetry of an electroweak theory of leptons and quarks with initially postulated symmetric fractional charges. The cancellation of gauge anomalies and the non-perturbative normalization of lepton charges proceed through the mixing of local and topological charges, the global $B-L$ measuring the induced charge associated with a unit of topological charge, and the mathematical replacement of the original fractional charges with the experimentally observed ones. The $U(1)_{B-L}$ symmetry of the SM with Dirac neutrinos is seen as a residual presymmetry. High-scale and low-scale seesaw mechanisms proposed to explain the mass of neutrinos are examined from the perspective of presymmetry, be they of Majorana or pseudo-Dirac type. We find that the tiny mass splitting in pseudo-Dirac neutrinos and the mass of heavy neutrinos ride on the opposite ends of the seesaw. We show that pseudo-Dirac neutrinos contain extra sterile neutrinos with imprints of presymmetry and for heavy ones we get constraints favoring the low-scale linear seesaw over the inverse variant.