Einstein spaces in five and seven dimensions and non-supersymmetric gauge theories

A one-parameter family of new solutions representing Einstein spaces in d=5,7 is presented, and used to construct non-supersymmetric backgrounds in type IIB and M-theory that asymptotically approach AdS5×S5 and AdS7×S4. Upon dimensional reduction, the latter gives a type IIA solution representing a 4-brane with Ramond-Ramond charge, which interpolates between the “near-horizon" non-extremal D4 brane and a geometry connected by T-duality to a new constant dilaton solution in type IIB. We discuss the possibility that M-theory on this space may be related to a (0,2) six-dimensional field theory on S1×S1, with fermions obeying antiperiodic boundary conditions in both circles.