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arXiv · 2608.08505

Coarse space preconditioning for Generalized Optimized Schwarz Methods. Part I: continuous case

Xavier Claeys
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Abstract

The Generalized Optimized Schwarz Method (GOSM) originally proposed in [Claeys, 2021] is a variant of Depr\'es algorithm, a domain decomposition strategy for the solution of harmonic wave propagation problems. It imposes transmission conditions through interfaces by means of a non-local exchange operator. Conducting our analysis at the continuous level, in an infinite dimensional setting, we propose a coarse space construction for the preconditioning of the GOSM formulation, and provide estimates for the convergence of GMRes applied to the preconditioned equation.

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Xavier Claeys. 2026-08-09. Coarse space preconditioning for Generalized Optimized Schwarz Methods. Part I: continuous case. https://arxiv.org/abs/2608.08505

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