Kato's inequality when $\Delta u$ is a measure

Haïm Brezis; Augusto C. Ponce

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arXiv · 1312.6498

Kato's inequality when $\Delta u$ is a measure

Haïm Brezis·Augusto C. Ponce

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Abstract

We extend the classical Kato's inequality in order to allow functions $u \in L^1_\mathrm{loc}$ such that $\Delta u$ is a Radon measure. This inequality has been applied by Brezis, Marcus, and Ponce to study the existence of solutions of the nonlinear equation $- \Delta u + g(u) = \mu$, where $\mu$ is a measure and $g : \mathbb{R} \to \mathbb{R}$ is an increasing continuous function.

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Haïm Brezis, Augusto C. Ponce. 2013-12-23. Kato's inequality when $\Delta u$ is a measure. https://arxiv.org/abs/1312.6498

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