Hidden Fine Tuning In The Quark Sector Of Little Higgs Models

TL;DR

This paper investigates how gauge interactions in Little Higgs models break the collective symmetry that protects the Higgs mass, revealing a fundamental challenge in maintaining naturalness in these models.

Contribution

It demonstrates that the breaking of collective symmetry by gauge interactions is a generic problem in Little Higgs models, extending previous findings.

Findings

Gauge interactions break the collective symmetry in top quark mass terms.

The problem is shown to be generic across different implementations.

Implications for the naturalness of Little Higgs models are discussed.

Abstract

In Little Higgs models a collective symmetry prevents the higgs from acquiring a quadratically divergent mass at one loop. We have previously shown that the couplings in the Littlest Higgs model introduced to give the top quark a mass do not naturally respect the collective symmetry. We extend our previous work showing that the problem is generic: it arises from the fact that the would be collective symmetry of any one top quark mass term is broken by gauge interactions.