Energy-momentum tensor for scalar fields coupled to the dilaton in two dimensions - art. no. 064007

We clarify some issues related to the evaluation of the mean value of the e nergy-momentum tensor for quantum scalar fields coupled to the dilaton fiel d in two-dimensional gravity. Because of this coupling, the energy-momentum tensor for matter is not conserved and therefore it is not determined by t he trace anomaly. We discuss different approximations for the calculation o f the energy-momentum tensor and show how to obtain the correct amount of H awking radiation. We also compute cosmological particle creation and quantu m corrections to the Newtonian potential. [S0556-2821(99)05104-8].