title: Non-nested multi-level solvers for finite element discretisations of mixed problems
abstract: We consider a general framework for analysing the convergence of multi-grid solvers applied to finite element discretisations of mixed problems, both of conforming and nonconforming type. As a basic new feature. our approach allows to use different finite element discretisations on each level of the multi-grid hierarchy. Thus, in our multi-level approach, accurate higher order finite element discretisations can be combined with fast multi-level solvers based on lower order (nonconforming) finite element discretisations. This leads to the design of efficient multi-level solvers for higher order finite element discretisations
keyphrases: non-nested multi-level solvers multi-level solvers finite element discretisations mixed problems multi-grid solvers higher order finite element discretisations