Additive Schwarz Methods for Elliptic Mortar Finite Element Problems

this paper we discuss two variants of the additive Schwarz method for solving systems of algebraic equations resulting from the approximation of second order elliptic problems with discontinuous coefficients. The discretization is obtained by using the mortar finite element method on nonmatching meshes, a technique which was first introduced by Bernardi, Maday, and Patera in [3]. The main characteristic of the method is that the ? This work has been supported in part by the Norwegian Research Council, grant 113492/42