Cosmological Expansion in the Randall-Sundrum Warped Compactification
  The cosmology of a brane-universe embedded in a higher dimensional bulk spacetime presents some peculiarities not seen in ordinary (3+1) dimensional gravity. I summarize the current understanding, with emphasis on the suggestion by Randall and Sundrum that the bulk is 5-D anti-deSitter space, leading to a solution of the weak scale hierarchy problem. 
J.M. Cline (McGill University)