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arXiv · 1704.05238

Babu\v{s}ka-Osborn techniques in discontinuous Galerkin methods: $L^2$-norm error estimates for unstructured meshes

Emmanuil Georgoulis·Charalambos Makridakis·Tristan Pryer
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Abstract

We prove the inf-sup stability of the interior penalty class of discontinuous Galerkin schemes in unbalanced mesh-dependent norms, under a mesh condition allowing for a general class of meshes, which includes many examples of geometrically graded element neighbourhoods. The inf-sup condition results in the stability of the interior penalty Ritz projection in $L^2$ as well as, for the first time, quasi-best approximations in the $L^2$-norm which in turn imply a priori error estimates that do not depend on the global maximum meshsize in that norm. Some numerical experiments are also given.

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Emmanuil Georgoulis, Charalambos Makridakis, Tristan Pryer. 2017-04-18. Babu\v{s}ka-Osborn techniques in discontinuous Galerkin methods: $L^2$-norm error estimates for unstructured meshes. https://arxiv.org/abs/1704.05238

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