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arXiv · 2411.03793

Quasi-Monte Carlo for partial differential equations with generalized Gaussian input uncertainty

Philipp A. Guth·Vesa Kaarnioja
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Abstract

There has been a surge of interest in uncertainty quantification for parametric partial differential equations (PDEs) with Gevrey regular inputs. The Gevrey class contains functions that are infinitely smooth with a growth condition on the higher-order partial derivatives, but which are nonetheless not analytic in general. Recent studies by Chernov and Le (Comput. Math. Appl., 2024, and SIAM J. Numer. Anal., 2024) as well as Harbrecht, Schmidlin, and Schwab (Math. Models Methods Appl. Sci., 2024) analyze the setting wherein the input random field is assumed to be uniformly bounded with respect to the uncertain parameters. In this paper, we relax this assumption and allow for parameter-dependent bounds. The parametric inputs are modeled as generalized Gaussian random variables, and we analyze the application of quasi-Monte Carlo (QMC) integration to assess the PDE response statistics using randomly shifted rank-1 lattice rules. In addition to the QMC error analysis, we also consider the dimension truncation and finite element errors in this setting.

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Philipp A. Guth, Vesa Kaarnioja. 2024-11-06. Quasi-Monte Carlo for partial differential equations with generalized Gaussian input uncertainty. https://arxiv.org/abs/2411.03793

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