  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.
