Yukawa Unification with Four Higgs Doublets in Supersymmetric GUT

TL;DR

This paper explores Yukawa coupling unification in supersymmetric GUT models with four Higgs doublets, showing it occurs at moderate tanβ and improves stability of electroweak symmetry breaking.

Contribution

It introduces a scenario with multiple Higgs doublets that alleviates LHC constraints and modifies unification conditions compared to traditional models.

Findings

Yukawa unification at medium tanβ (~30) reduces threshold corrections.

Additional Higgs doublets lower sensitivity of electroweak symmetry breaking.

Scenario compatible with current LHC constraints.

Abstract

We discuss the Yukawa coupling unification, a very interesting prediction of the grand unified theory, in the context of scenarios with more than one pair of Higgs doublet since the current LHC constraint has become a problem for the Yukawa unification scenarios with just one pair of Higgs doublet. More than one pair of Higgs doublets can easily arise in missing partner mechanism which solves the doublet-triplet splitting problem. In such a scenario, the Yukawa unification occurs at a medium $\tan\beta$ value, e.g., $\sim$ 30, which corresponds to much smaller threshold corrections compared to usual large $\tan\beta$ scenario for $t-b-\tau$ unification in the context of SO(10) and $b-\tau$ unification in the context of SU(5) models. Further, we show that an additional Higgs doublet pair lowers the sensitivity of the radiative symmetry breaking of the electroweak vacuum.