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arXiv · 2509.00932

Sufficient conditions for strong discrete maximum principles in finite element solutions of linear and semilinear elliptic equations

Andrei Draganescu·L. Ridgway Scott
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Abstract

We introduce a novel technique for proving global strong discrete maximum principles for finite element discretizations of linear and semilinear elliptic equations for cases when the common, matrix-based sufficient conditions are not satisfied. The basic argument consists of extending the strong form of discrete maximum principle from macroelements to the entire domain via a connectivity argument. The method is applied to discretizations of elliptic equations with certain pathological meshes, and to semilinear elliptic equations.

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Andrei Draganescu, L. Ridgway Scott. 2025-08-31. Sufficient conditions for strong discrete maximum principles in finite element solutions of linear and semilinear elliptic equations. https://arxiv.org/abs/2509.00932

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