Radiative Fermion Mass Hierarchy in a Non-supersymmetric Unified Theory

TL;DR

This paper presents a non-supersymmetric grand unified model where fermion mass hierarchies arise radiatively, linking lightest family masses to high-scale physics and unified gauge symmetry, with implications for neutrino mixing.

Contribution

It introduces a simple, realistic, and predictive model demonstrating how radiative processes can generate fermion mass hierarchies in grand unified theories.

Findings

Fermion masses are determined by physics at the unification scale.

The model predicts relations among quark and lepton masses.

A 'doubly lopsided' structure explains bilarge neutrino mixing.

Abstract

In non-supersymmetric grand unified models a ``radiative fermion mass hierarchy" can be achieved in which the spectrum of quark and lepton masses is determined entirely by physics at the unification scale, with many relations following from the unified gauge symmetry, and with the masses of the lightest family arising from loops. A simple, realistic, and predictive model of this kind is presented. A "doubly lopsided" structure, known to lead to bilarge neutrino mixing, plays a crucial role in the radiative hierarchy.