Gauge Coupling Unification in simplified Grand Gauge-Higgs Unification

TL;DR

This paper demonstrates that in a five-dimensional SU(6) gauge theory with orbifold compactification and localized kinetic terms, gauge coupling unification can be achieved around 10^14 GeV, lower than traditional GUT scales.

Contribution

It introduces a simplified grand gauge-Higgs unification model with boundary fermions and bulk fields, showing perturbative unification at an intermediate scale.

Findings

Gauge coupling unification at ~10^14 GeV

Perturbative unification achieved with bulk contributions

Unification scale lower than 4D GUTs

Abstract

Grand gauge-Higgs unification of five dimensional SU(6) gauge theory on an orbifold $S^1/Z_2$ with localized gauge kinetic terms is discussed. The Standard model (SM) fermions on the boundaries and some massive bulk fermions coupling to the SM fermions on the boundary are introduced. Taking the power-law running contributions from the bulk fields into account, perturbative gauge coupling unification is shown to be realized at around $10^{14}$ GeV, which is a few order smaller than the unification scale of four dimensional grand unified theories.