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arXiv · 2007.08462

Existence and improved regularity for a nonlinear system with collapsing ellipticity

Edgard A. Pimentel·José Miguel Urbano
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Abstract

We study a nonlinear system made up of an elliptic equation of blended singular/degenerate type and Poisson's equation with a lowly integrable source. We prove the existence of a weak solution in any space dimension and, chiefly, derive an improved $\mathcal{C}^{1,\text{log-Lip}}$-regularity estimate using tangential analysis methods. The system illustrates a sophisticated version of the proverbial thermistor problem and our results are new even in simpler modelling scenarios.

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Edgard A. Pimentel, José Miguel Urbano. 2020-07-16. Existence and improved regularity for a nonlinear system with collapsing ellipticity. https://arxiv.org/abs/2007.08462

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