# A scalable and robust vertex-star relaxation for high-order FEM

@inproceedings{Brubeck2021ASA, title={A scalable and robust vertex-star relaxation for high-order FEM}, author={Pablo D Brubeck and Patrick E. Farrell}, year={2021} }

Pavarino proved that the additive Schwarz method with vertex patches and a loworder coarse space gives a p-robust solver for symmetric and coercive problems [33]. However, for very high polynomial degree it is not feasible to assemble or factorize the matrices for each patch. In this work we introduce a direct solver for separable patch problems that scales to very high polynomial degree on tensor product cells. The solver constructs a tensor product basis that diagonalizes the blocks in the… Expand

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