Auxiliary space AMG for H(curl) problems

In this paper we review a number of auxiliary space based preconditioners for the second order definite and semi-definite Maxwell problems discretized with the lowest order Nédélec finite elements. We discuss the parallel implementation of the most promising of these methods, the ones derived from the recent Hiptmair-Xu (HX) auxiliary space decomposition [13]. An extensive set of numerical experiments demonstrate the scalability of our implementation on large-scale H(curl) problems