Effective Lagrangians for physical degrees of freedom in the Randall-Sundrum model

TL;DR

This paper derives the effective four-dimensional Lagrangian for the Randall-Sundrum model with two branes, analyzing gauge invariance, mass spectra, and couplings of gravity to matter.

Contribution

It provides a detailed derivation of the second variation Lagrangian and explores how the effective theory varies on different branes in the model.

Findings

Effective 4D theory differs on various branes.

Calculated observable mass spectra of physical modes.

Analyzed couplings of 5D gravity to matter.

Abstract

We derive the second variation Lagrangian of the Randall-Sundrum model with two branes, study its gauge invariance and diagonalize it in the unitary gauge. We also show that the effective four-dimensional theory looks different on different branes and calculate the observable mass spectra and the couplings of the physical degrees of freedom of 5-dimensional gravity to matter.