Cosmology in the Randall-Sundrum brane world scenario

The cosmology of the Randall-Sundrum scenario for a positive tension brane in a 5-D Universe with localized gravity has been studied extensively recen tly. Here we extend it to more general situations. We consider the time-dep endent situation where the two sides of the brans are different AdS/Schwarz schild spaces. We show that the expansion rate in these models during infla tion could be larger than in brane worlds with compactified extra dimension s of fixed size. The enhanced expansion rate could lead to the production o f density perturbations of substantially larger amplitude. (C) 2000 Elsevie r Science B.V. All rights reserved.