Sharp Condition Number Estimates for the Symmetric 2-Lagrange Multiplier Method

Abstract

Domain decomposition methods are used to find the numerical solution of large boundary value problems in parallel. In optimized domain decomposition methods, one solves a Robin subproblem on each subdomain, where the Robin parameter a must be tuned (or optimized) for good performance.We show that the 2-Lagrange multiplier method can be analyzed using matrix analytical techniques and we produce sharp condition number estimates. © Springer-Verlag Berlin Heidelberg 2013.