Schwinger terms in Weyl-invariant and diffeomorphism-invariant 2-d scalar field theory

Abstract

We compute the Schwinger terms in the energy-momentum tensor commutator algebra from the anomalies present in Weyl-invariant and diffeomorphism-invariant effective actions for two dimensional massless scalar fields in a gravitational background. We find that the Schwinger terms are not sensitive to the regularization procedure and that they are independent of the background metric.Comment: 8 pages, RevTex. Conclusions and references added. To appear in Phys. Rev.