de Sitter space, (D)pp-Waves and a star-Matrix model

Abstract

We consider de Sitter spacetime solutions and the corresponding de Sitter kind of plane-wave solutions in M* theory. We attempt to write down corresponsing matrix model which is found to have explicit negative energy mass terms as well as negative energy kinetic terms for the matrix fields.

9 pages,v2: small change in sign and typo fixed,v3: many important corrections