Abstract

We consider quantization of open string theories in linear dilaton and constant antisymmetric tensor backgrounds and discuss the noncommutativity of space-time coordinates arising in such theories, including their relationship with light-like noncommutativity as well as backgrounds with null isometries. It is argued that the results can also be understood using space-time equations of motion of the string modes. We then present N = 2 supersymmetric generalization of these theories and the associated noncommutative structure. Present address, Regular Associate of the Abdus Salam ICTP Permanent addressThe study of string propagation in background fields has been an active area of research for a long time [1]. One such consistent set of background includes a general target space metric, antisymmetric tensor field and a linear dilaton. String theories with linear dilaton background [2] is interesting from the point of view of D-branes [3, 4] as well as in conformal field theory (CFT), using their free field realizations. They also play a role in understanding the cosmological implications of string theory[5] as well as in