Effective theories of gauge-Higgs unification models in warped spacetime

TL;DR

This paper derives simplified four-dimensional effective theories for gauge-Higgs unification models in warped spacetime, revealing the nonlinear Higgs sector structure and explaining coupling suppression factors.

Contribution

It provides a new, simplified form of the effective action that explicitly shows the nonlinear Higgs structure and the origin of coupling suppressions in gauge-Higgs unification models.

Findings

Effective 4D theories expressed in simple form

Explicit demonstration of nonlinear Higgs sector

Clarification of Higgs coupling suppression mechanisms

Abstract

We derive four-dimensional (4D) effective theories of the gauge-Higgs unification models in the warped spacetime. The effective action can be expressed in a simple form by neglecting subleading corrections to the wave functions. We have shown in our previous works that some Higgs couplings to the other fields are suppressed by factors that depend on $\bar{\theta}_H$ from the values in the standard model. Here $\bar{\theta}_H$ is the Wilson line phase along the fifth dimension, which characterizes the electroweak symmetry breaking. The effective action derived here explicitly shows a nonlinear structure of the Higgs sector, which clarifies the origins of those suppression factors.