Stabilization of branes in a coslogical setting

Abstract

We study some cosmological consequences of the five dimensional, two brane Randall-Sundrum scenario. We integrate over the extra dimensions and in four dimensions the action reduces to that of scalar tensor gravity. The radius of the compact extra dimension is taken to be time dependent. It is shown that the radius of the extra dimension rapidly approaches a constant nonzero separation of branes. A radion dominated universe cannot undergo accelerated expansion in the absence of a potential. It is shown that a simple quadratic potential with minimum at zero leads to constant nonzero separation of branes in a similar level but now accelerated expansion is possible. After stabilization the quadratic potential contributes an effective cosmological constant term. We show that with a suitable tuning of parameters the requirements for solving the hierarchy problem and getting an effective dark energy can be satisfied simultaneously.