RENORMALIZATION-GROUP IMPROVED EFFECTIVE POTENTIAL FOR INTERACTING THEORIES WITH SEVERAL MASS SCALES IN CURVED SPACETIME

The renormalization group (RG) is used in order to obtain the RG impro ved effective potential in curved spacetime. This potential is explici tly calculated for the Yukawa model and for scalar electrodynamics, i. e. theories with several (namely, more than one) mass scales, in a spa ce of constant curvature. Using the lambda phi(4)-theory on a general curved spacetime as an example, we show how it is possible to find the RG improved effective Lagrangian in curved spacetime. As specific app lications, we discuss the possibility of curvature-induced phase trans itions in the Yukawa model and the effective equations (back-reaction problem) for the lambda phi(4)-theory on a De Sitter background.