A Predictive and Testable Unified Theory of Fermion Masses, Mixing and Leptogenesis

TL;DR

This paper develops a minimal non-supersymmetric SO(10) GUT model that links fermion masses, mixing, leptogenesis, proton decay, and gravitational wave signals, providing testable predictions for future experiments.

Contribution

It presents a unified framework connecting fermion properties, baryon asymmetry, and cosmic strings, with detailed scale calculations and experimental predictions.

Findings

Identifies parameter regions compatible with leptogenesis and fermion data.

Predicts proton decay rates within reach of upcoming experiments.

Foresees gravitational wave signals from cosmic strings detectable by future observatories.

Abstract

We consider a minimal non-supersymmetric $SO(10)$ Grand Unified Theory (GUT) model that can reproduce the observed fermionic masses and mixing parameters of the Standard Model. We calculate the scales of spontaneous symmetry breaking from the GUT to the Standard Model gauge group using two-loop renormalisation group equations. This procedure determines the proton decay rate and the scale of $U(1)_{B-L}$ breaking, which generates cosmic strings and the right-handed neutrino mass scales. Consequently, the regions of parameter space where thermal leptogenesis is viable are identified and correlated with the fermion masses and mixing, the neutrinoless double beta decay rate, the proton decay rate, and the gravitational wave signal resulting from the network of cosmic strings. We demonstrate that this framework, which can explain the Standard Model fermion masses and mixing and the observed baryon asymmetry, will be highly constrained by the next generation of gravitational wave detectors and neutrino oscillation experiments which will also constrain the proton lifetime.