Effect of Bare Mass on the Hosotani Mechanism

TL;DR

This paper investigates how bare mass terms for matter fields influence gauge symmetry breaking via the Hosotani mechanism, revealing critical mass values where the vacuum structure and symmetry patterns change.

Contribution

It demonstrates that bare mass terms alter the gauge symmetry patterns in the Hosotani mechanism, providing a detailed analysis of an SU(2) model with massive adjoint fermions and supersymmetric extensions.

Findings

Vacuum structure changes at critical mass values

Gauge symmetry breaking patterns differ from massless cases

Supersymmetry can be broken by bare mass terms

Abstract

It is pointed out that the existence of bare mass terms for matter fields changes gauge symmetry patterns through the Hosotani mechanism. As a demonstration, we study an SU(2) gauge model with massive adjoint fermions defined on $M^4\otimes S^1$. It turns out that the vacuum structure changes at certain critical values of $mL$, where $m~(L)$ stands for the bare mass (the circumference of $S^1$). The gauge symmetry breaking patterns are different from models with massless adjoint fermions. We also consider a supersymmmetric SU(2) gauge model with adjoint hypermultiplets, in which the supersymmetry is broken by bare mass terms for the gaugino and squark fields instead of the Scherk-Schwarz mechanism.