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arXiv · 2506.22128

Weak comparison principle for widely degenerate elliptic equations

Antonio Giuseppe Grimaldi·Stefania Russo
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Abstract

We prove a comparison principle for local weak solutions to a class of widely degenerate elliptic equations of the form \begin{equation} -\text{div} \left( \left(|Du|-1 \right)^{p-1}_+\frac{Du}{|Du|} \right) = f(x,u) \qquad \text{ in } \Omega,\notag \end{equation} where $p \ge 2$ and $\Omega$ is an open subset of $\mathbb{R}^{n}$, $n\geq2$. Moreover, we establish some second order regularity results of the solutions, that yields a weighted Sobolev inequality with widely degenerate weights.

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Antonio Giuseppe Grimaldi, Stefania Russo. 2025-06-27. Weak comparison principle for widely degenerate elliptic equations. https://arxiv.org/abs/2506.22128

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