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arXiv · 2001.03266

Concavity of solutions to degenerate elliptic equations on the sphere

Mat Langford·Julian Scheuer
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Abstract

We prove the concavity of classical solutions to a wide class of degenerate elliptic differential equations on strictly convex domains of the unit sphere. The proof employs a suitable two-point maximum principle, a technique which originates in works of Korevaar, Kawohl and Kennington for equations on Euclidean domains. We emphasize that no differentiability of the differential operator is needed, but only some monotonicity and concavity properties.

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Mat Langford, Julian Scheuer. 2020-01-10. Concavity of solutions to degenerate elliptic equations on the sphere. https://doi.org/10.1080/03605302.2020.1857404

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