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arXiv · 2308.03223

Discrete weak duality of hybrid high-order methods for convex minimization problems

Ngoc Tien Tran
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Abstract

This paper derives a discrete dual problem for a prototypical hybrid high-order method for convex minimization problems. The discrete primal and dual problem satisfy a weak convex duality that leads to a priori error estimates with convergence rates under additional smoothness assumptions. This duality holds for general polyhedral meshes and arbitrary polynomial degrees of the discretization. A novel postprocessing is proposed and allows for a~posteriori error estimates on regular triangulations into simplices using primal-dual techniques. This motivates an adaptive mesh-refining algorithm, which performs superiorly compared to uniform mesh refinements.

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Ngoc Tien Tran. 2023-08-06. Discrete weak duality of hybrid high-order methods for convex minimization problems. https://doi.org/10.1137/23m1594534

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