Early Inflation and Cosmology in Theories with Sub-Millimeter Dimensions

We discuss early cosmology in theories where the fundamental Planck mass is close to the TeV scale. In such theories the standard model fields are localized to a (3 + 1)-dimensional wall with n new transverse sub-millimeter sized spatial dimensions. The topics touched upon include: early inflation that occurs while the size of the new dimensions are still small, the spectrum and magnitude of density perturbations, the post-inflation era of contraction of our world while the internal dimensions evolve to their final ''large'' radius, and the production of gravitons in the bulk during these two eras. The radion moduli problem is also discussed