A Cosmological Solution to the Doublet-Triplet Splitting Problem

TL;DR

This paper introduces a unified model addressing multiple fundamental issues in grand unified theories, utilizing axion-like particles whose properties could be tested in future experiments.

Contribution

It presents a novel mechanism involving two axion-like particles that simultaneously solve the doublet-triplet splitting, hierarchy, and strong CP problems.

Findings

Proposes a new axion-based solution to GUT problems.

Predicts detectable axion-like particles in upcoming experiments.

Links axion properties to cosmological and particle physics observations.

Abstract

We propose a model that provides a simultaneous solution to the doublet-triplet splitting problem of grand unified theories, the electroweak hierarchy problem and the strong CP problem. The mechanism is based on the dynamics of two axion-like particles that would crunch the universe at the time of the QCD phase transition if triplets were light or had a VEV or if doublets were heavy or did not have a VEV. The only trace left at low energies are these two axion-like particles. They are weakly coupled to the Standard Model and could be detected at upcoming axion experiments or by a combination of neutron EDM measurements and the astrophysical detection of fuzzy dark matter.