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arXiv · 2006.07192

Concavity properties of solutions to Robin problems

Graziano Crasta·Ilaria Fragalà
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Abstract

We prove that the Robin ground state and the Robin torsion function are respectively log-concave and $\frac{1}{2}$-concave on an uniformly convex domain $\Omega\subset \mathbb{R}^N$ of class $\mathcal{C}^m$, with $[m -\frac{ N}{2}]\geq 4$, provided the Robin parameter exceeds a critical threshold. Such threshold depends on $N$, $m$, and on the geometry of $\Omega$, precisely on the diameter and on the boundary curvatures up to order $m$.

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Graziano Crasta, Ilaria Fragalà. 2020-06-12. Concavity properties of solutions to Robin problems. https://arxiv.org/abs/2006.07192

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