A supersymmetric and smooth compactification of M-theory to AdS5

We obtain smooth M-theory solutions whose geometry is a warped product of AdS(5) and a compact internal space that can be viewed as an S-4 bundle over S-2. The bundle can be trivial or twisted, depending on the even or odd values of the two diagonal monopole charges. The solution preserves M = 2 supersymmetry and is dual to an M = 1, D = 4 superconformal field theory, providing a concrete framework to study the AdS(5)/CFT4 correspondence in M-theory. We construct analogous embeddings of AdS(4), AdS(3) and AdS(2) in massive type IIA, type IIB and M-theory, respectively. The internal spaces have generalized holonomy and can be viewed as S-n bundles over S-2 for n = 4, 5 and 7. Surprisingly, the dimensions of spaces with generalized holonomy includes D = 9. We also obtain a large class of solutions of AdS x H-2. (C) 2003 Published by Elsevier B.V.