  There are various different descriptions of Randall-Sundrum (RS) braneworlds.
Here we present a unified view of the braneworld based on the gradient
expansion approach. In the case of the single-brane model, we reveal the
relation between the geometrical and the AdS/CFT approach. It turns out that
the high energy and the Weyl term corrections found in the geometrical approach
merge into the CFT matter correction found in the AdS/CFT approach. We also
clarify the role of the radion in the two-brane system. It is shown that the
radion transforms the Einstein theory with Weyl correction into the conformally
coupled scalar-tensor theory where the radion plays the role of the scalar
field.
