EINSTEIN-SPACES IN 5 AND 7 DIMENSIONS AND NONSUPERSYMMETRIC GAUGE-THEORIES

A one-parameter family of new solutions representing Einstein spaces i n d = 5,7 is presented, and used to construct non-supersymmetric backg rounds in type IIB and M-theory that asymptotically approach AdS(5) x S-5 and AdS(7) x S-4. Upon dimensional reduction, the latter gives a t ype IIA solution representing a 4-brane with Ramond-Ramond charge, whi ch 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-thcory on this space ma y be related to a (0,2) six-dimensional field theory on S-1 x S-1, wit h fermions obeying antiperiodic boundary conditions in both circles. ( C) 1998 Elsevier Science B.V. All rights reserved.