Electroweak Constraints on Warped Geometry in Five Dimensions and Beyond

TL;DR

This paper analyzes how warped extra dimensions in five or more dimensions affect electroweak observables, highlighting the importance of gauge-Higgs couplings and warp factors in constraining new physics models.

Contribution

It provides a comprehensive study of tree level electroweak corrections in warped geometries, including D>5 spaces, and identifies how warp factors influence these corrections.

Findings

Large gauge-Higgs couplings are typical in warped spaces addressing the hierarchy problem.

EW corrections increase when the warp factor contracts towards the IR brane.

The Klebanov Strassler solution exemplifies a geometry with significant EW corrections.

Abstract

Here we consider the tree level corrections to electroweak (EW) observables from standard model (SM) particles propagating in generic warped extra dimensions. The scale of these corrections is found to be dominated by three parameters, the Kaluza-Klein (KK) mass scale, the relative coupling of the KK gauge fields to the Higgs and the relative coupling of the KK gauge fields to fermion zero modes. It is found that 5D spaces that resolve the hierarchy problem through warping typically have large gauge-Higgs coupling. It is also found in $D>5$ where the additional dimensions are warped the relative gauge-Higgs coupling scales as a function of the warp factor. If the warp factor of the additional spaces is contracting towards the IR brane, both the relative gauge-Higgs coupling and resulting EW corrections will be large. Conversely EW constraints could be reduced by finding a space where the additional dimension's warp factor is increasing towards the IR brane. We demonstrate that the Klebanov Strassler solution belongs to the former of these possibilities.