Yang-Mills Localization in Warped Space

TL;DR

This paper introduces a mechanism for localizing non-Abelian gauge fields in warped space, addressing gauge invariance issues and exploring scalar localization, with implications for gauge-Higgs unification models.

Contribution

It presents a novel localization method for non-Abelian gauge fields in warped space that maintains gauge invariance through boundary interactions and discusses scalar sector issues.

Findings

Zero mode gauge fields can be localized with exponential profiles.

Gauge invariance is restored via boundary kinetic terms.

Scalar zero modes can be localized anywhere in the bulk.

Abstract

We present a mechanism to localize zero mode non-Abelian gauge fields in a slice of AdS_5. As in the U(1) case, bulk and boundary mass terms allow for a massless mode with an exponential profile that can be localized anywhere in the bulk. However in the non-Abelian extension, the cubic and quartic zero mode gauge couplings do not match, implying a loss of 4D gauge invariance. We show that the symmetry can be restored at the nonlinear level by considering brane-localized interactions, which are added in a gauge invariant way using boundary kinetic terms. Possible issues related to the scalar sector of the theory, such as strong coupling and ghosts, are also discussed. Our approach is then compared with other localization mechanisms motivated by dilaton gravity and deconstruction. Finally, we show how to localize the scalar component A_5 zero mode anywhere in the bulk which could be relevant in gauge-Higgs unification models.