Quasi-Localization of Gravity by Resonant Modes

TL;DR

This paper investigates how gravity behaves in brane models with extra dimensions, showing that resonant modes can temporarily localize gravity on the brane, but eventually five-dimensional gravity dominates at large scales.

Contribution

It introduces the concept of quasi-localization of gravity via resonant modes in non-factorizable geometries, providing a classification of effective gravity theories on the brane.

Findings

Existence of a zero-energy graviton resonance in asymptotically flat brane models.

Gravity appears four-dimensional at intermediate scales due to the resonance.

At large scales, five-dimensional gravity laws are recovered as the resonance decays.

Abstract

We examine the behaviour of gravity in brane theories with extra dimensions in a non-factorizable geometry. We find that for metrics which are asymptotically flat far from the brane there is a resonant graviton mode at zero energy. The presence of this resonance ensures quasi-localization of gravity, whereby at intermediate scales the gravitational laws on the brane are approximately four dimensional. However, for scales larger than the lifetime of the graviton resonance the five dimensional laws of gravity will be reproduced due to the decay of the four dimensional graviton. We also present a simple classification of the possible types of effective gravity theories on the brane that can appear for general non-factorizable background theories.