Confronting SO(10) GUTs with proton decay and gravitational waves

TL;DR

This paper explores specific non-supersymmetric SO(10) grand unified theories, predicting proton decay and gravitational wave signals from cosmic strings, by calculating unification and symmetry breaking scales through two-loop renormalization group analysis.

Contribution

It identifies SO(10) breaking chains compatible with gauge unification and predicts associated proton decay and gravitational wave signals, including their correlations.

Findings

Certain SO(10) chains predict observable proton decay lifetimes.

Some chains generate cosmic strings with detectable gravitational waves.

Null results constrain the viable GUT breaking scenarios.

Abstract

Grand Unified Theories (GUT) predict proton decay as well as the formation of cosmic strings which can generate gravitational waves. We determine which non-supersymmetric $SO(10)$ breaking chains provide gauge unification in addition to a gravitational signal from cosmic string decay. We calculate the GUT and intermediate scales for these $SO(10)$ breaking chains by solving the renormalisation group equations at the two-loop level. This analysis predicts the GUT scale, hence the proton lifetime, in addition to the scale of cosmic string generation and thus the associated gravitational wave signal. We determine which $SO(10)$ breaking chains survive in the event of the null results of the next generation of gravitational waves and proton decay searches and determine the correlations between proton decay and gravitational waves scales if these observables are measured.