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arXiv · 0709.3531

On the Hopf Lemma

YanYan Li·L. Nirenberg
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Abstract

The Hopf Lemma for second order elliptic operators is proved to hold in domains with $C^{1,α}$, and even less regular, boundaries. It need not hold for $C^1$ boundaries. Corresponding results are proved for second order parabolic operators.

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YanYan Li, L. Nirenberg. 2007-09-28. On the Hopf Lemma. https://arxiv.org/abs/0709.3531

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