Nonsmooth problems; variational inequalities.

Many problems in physics and in other applications cannot be formulated as equations but have some more complicated structure, usually of a so-called complementarity problem. From the abstract viewpoint, the equations are replaced by inclusions involving set-valued mappings. We confine ourselves to a rather simple case (but still having wide applications) which involves set-valued mappings whose “set-valued part” can be described as a subdifferential of a convex but nonsmooth potential. Recall that we consider, if not said otherwise, V reflexive. [ABSTRACT FROM AUTHOR]