ULTRAVIOLET AND INFRARED FINITENESS IN 2-DIMENSIONAL CURVED SPACE-TIME

Different models of field theories in two dimensions can be described by the action Tr integral phi F. In the presence of a curved backgroun d, we construct local supersymmetry-like transformations under which t he action is invariant. Furthermore, by analyzing the cohomology of th e theory we show the absence of anomalies. Also the ultraviolet and th e infrared finiteness of the theory are proven at all orders of pertur bation theory. (C) 1998 Academic Press.