Probe Brane Dynamics and the Cosmological Constant

TL;DR

This paper explores the dynamics and stability of brane worlds in relation to the cosmological constant, showing that small instabilities are negligible for our universe's tiny cosmological constant.

Contribution

It analyzes the stability of stationary brane solutions and probe brane dynamics within a brane world framework addressing the cosmological constant problem.

Findings

Small perturbations cause instability but are harmless for tiny cosmological constants.

Radion stabilizing potentials can be incorporated for more realistic models.

The scenario offers insights into the hierarchy problem and universe stability.

Abstract

Recently a brane world perspective on the cosmological constant and the hierarchy problems was presented. Here, we elaborate on some aspects of that particular scenario and discuss the stability of the stationary brane solution and the dynamics of a probe brane. Even though the brane is unstable under a small perturbation from its stationary position, such instability is harmless when the 4-D cosmological constant is very small, as is the case of our universe. One may also introduce radion stabilizing potentials in a more realistic scenario.