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arXiv · 0910.0322

Partial results on extending the Hopf Lemma

YanYan Li·Louis Nirenberg
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Abstract

In [1], Theorem 3, the authors proved, in one dimension, a generalization of the Hopf Lemma, and the question arose if it could be extended to higher dimensions. In this paper we present two conjectures as possible extensions, and give a very partial answer. We write this paper to call attention to the problem.

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YanYan Li, Louis Nirenberg. 2009-10-02. Partial results on extending the Hopf Lemma. https://arxiv.org/abs/0910.0322

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