Continuous differentiability of a weak solution to very singular elliptic equations involving anisotropic diffusivity

Shuntaro Tsubouchi

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arXiv · 2208.14640

Continuous differentiability of a weak solution to very singular elliptic equations involving anisotropic diffusivity

Shuntaro Tsubouchi

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Abstract

In this paper we consider a very singular elliptic equation that involves an anisotropic diffusion operator, including one-Laplacian, and is perturbed by a $p$-Laplacian-type diffusion operator with $1<p<\infty$. This equation seems analytically difficult to handle near a facet, the place where the gradient vanishes. Our main purpose is to prove that weak solutions are continuously differentiable even across the facet. Here it is of interest to know whether a gradient is continuous when it is truncated near a facet. To answer this affirmatively, we consider an approximation problem, and use standard methods including De Giorgi's truncation and freezing coefficient methods.

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Shuntaro Tsubouchi. 2022-08-31. Continuous differentiability of a weak solution to very singular elliptic equations involving anisotropic diffusivity. https://arxiv.org/abs/2208.14640

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