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arXiv · 1409.5254

Analysis of a Time Multigrid Algorithm for DG-Discretizations in Time

Martin J. Gander·Martin Neumüller
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Abstract

We present and analyze for a scalar linear evolution model problem a time multigrid algorithm for DG-discretizations in time. We derive asymptotically optimized parameters for the smoother, and also an asymptotically sharp convergence estimate for the two grid cycle. Our results hold for any A-stable time stepping scheme and represent the core component for space-time multigrid methods for parabolic partial differential equations. Our time multigrid method has excellent strong and weak scaling properties for parallelization in time, which we show with numerical experiments.

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Martin J. Gander, Martin Neumüller. 2014-09-18. Analysis of a Time Multigrid Algorithm for DG-Discretizations in Time. https://arxiv.org/abs/1409.5254

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