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arXiv · 2605.12417

A Least-Squares Weak Galerkin Method for Second-Order Elliptic Equations in Non-Divergence Form

Chunmei Wang·Shangyou Zhang
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Abstract

This article proposes a novel least-squares weak Galerkin (LS-WG) method for second-order elliptic equations in non-divergence form. The approach leverages a locally defined discrete weak Hessian operator constructed within the weak Galerkin framework. A key feature of the resulting algorithm is that it yields a symmetric and positive definite linear system while remaining applicable to general polygonal and polyhedral meshes. We establish optimal-order error estimates for the approximation in a discrete $H^2$-equivalent norm. Finally, comprehensive numerical experiments are presented to validate the theoretical analysis and demonstrate the efficiency and robustness of the method.

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Chunmei Wang, Shangyou Zhang. 2026-05-12. A Least-Squares Weak Galerkin Method for Second-Order Elliptic Equations in Non-Divergence Form. https://arxiv.org/abs/2605.12417

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