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arXiv · 2512.06166

A polynomial dimension-dependence analysis of Bramble--Pasciak--Xu preconditioners

Boou Jiang·Jongho Park·Jinchao Xu
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Abstract

We investigate the dimension dependence of Bramble--Pasciak--Xu (BPX) preconditioners for high-dimensional partial differential equations and establish that the condition numbers of BPX-preconditioned systems grow only polynomially with the spatial dimension. Our analysis requires a careful derivation of the dimension dependence of several fundamental tools in the theory of finite element methods, including elliptic regularity, the Bramble--Hilbert lemma, trace inequalities, and inverse inequalities. We further analyze an averaged Scott--Zhang-type quasi-interpolation operator, and show that its associated constants scale polynomially with the dimension. Building on these ingredients, we prove a multilevel norm equivalence theorem and derive a BPX preconditioner with explicit polynomial bounds on its dimensional dependence. The analysis is motivated in part by recent tensor and quantum finite element methods, where dimension-explicit conditioning estimates for BPX preconditioners play an important role.

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Boou Jiang, Jongho Park, Jinchao Xu. 2025-12-05. A polynomial dimension-dependence analysis of Bramble--Pasciak--Xu preconditioners. https://arxiv.org/abs/2512.06166

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