A clockwork solution to the doublet-triplet splitting problem

Gero Von Gersdorff

doi:10.1016/j.physletb.2020.136039

Abstract

Maybe the biggest puzzle in grand unified theories (GUTs) is the apparent large splitting of the doublet and triplet Higgs masses. We suggest a novel mechanism to solve this puzzle, which relies on the clockwork mechanism to generate large hierarchies from order-one numbers. The tension between gauge coupling unification and proton lifetime from minimal SU(5) GUTs is also removed in this scenario, and the theory remains perturbative until the Planck scale. We comment on a possible extra dimensional implementation of the idea.

Highlights

The quantum numbers of the Standard Model (SM) fermions strongly suggest the existence of a unified gauge group such as SU (5) or SO(10)
The minimal supersymmetric (SUSY) extension of the SM, the MSSM, the gauge couplings unify with a good accuracy at a scale of the order of ∼ 1016 GeV [1,2,3,4,5,6]
As we will review such a splitting of doublets and triplets is highly unnatural in the minimal models, i.e., it requires an accurate cancellation of seemingly unrelated parameters

Summary

Introduction

The quantum numbers of the Standard Model (SM) fermions strongly suggest the existence of a unified gauge group such as SU (5) or SO(10). The minimal supersymmetric (SUSY) extension of the SM, the MSSM, the gauge couplings unify with a good accuracy at a scale of the order of ∼ 1016 GeV [1,2,3,4,5,6]. In the simplest SU (5) scenario, the Higgs doublets unify with triplets in fundamental representations of the gauge group.

Results

Conclusion