für Mathematik in den Naturwissenschaften Leipzig Strict convexity of the free energy for non - convex

We consider a gradient interface model on the lattice with interaction potential which is a non-convex perturbation of a convex potential. We show using a one-step multiple scale analysis the strict convexity of the surface tension at high temperature. This is an extension of Funaki and Spohn’s result [10], where the strict convexity of potential was crucial in their proof. AMS 2000 Subject Classification. 60K35, 82B24, 35J15