On the Perturbative Approach in the Randall-Sundrum Model

TL;DR

This paper investigates a perturbative method for analyzing gauge and fermion spectra in the Randall-Sundrum model with electroweak symmetry breaking, providing explicit analytical expressions and validating the approach against exact results.

Contribution

It extends existing studies by deriving explicit analytical formulas in a covariant gauge for loop calculations and compares perturbative results with exact solutions for gauge bosons and fermions.

Findings

Perturbative approach matches exact spectra for gauge bosons and fermions.

Explicit analytical expressions in covariant R_xi gauge are derived.

Validation supports the use of perturbation methods in Randall-Sundrum models.

Abstract

We study a SU(2)_L x U(1)_Y gauge theory in the Randall-Sundrum background, including electroweak symmetry breaking due to a brane-localized Higgs sector. We work in the decomposed four dimensional theory and treat the symmetry breaking effects as a perturbation. Although there is an exact approach, this method is widely used and quite intuitive. We extend existing studies by giving explicit analytical expressions in a covariant R_xi gauge, needed for loop calculations in the decomposed theory. The perturbative approach is also applied to fermions and a comparison of the gauge boson and fermion spectra with the exact results is presented, validating the perturbative method used in the literature.