The normal derivative lemma and surrounding issues

D. E. Apushkinskaya   ; A. I. Nazarov

Trudy Matematicheskogo Instituta imeni V.A. Steklova, Tome 77 (2022) no. 2, pp. 189-249

Résumé

In this survey we describe the history and current state of one of the key areas in the qualitative theory of elliptic partial differential equations related to the strong maximum principle and the boundary point principle (normal derivative lemma). Bibliography: 234 titles.

Détail

Keywords: strong maximum principle, normal derivative lemma, Hopf–Oleinik lemma, Harnack inequality, Aleksandrov–Bakelman maximum principle.

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