Regularity for almost minimizers with free boundary

Guy David; Tatiana Toro

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arXiv · 1306.2704

Regularity for almost minimizers with free boundary

Guy David·Tatiana Toro

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Abstract

In this paper we study the local regularity of almost minimizers of the functional \begin{equation*} J(u)=\int_Ω|\nabla u(x)|^2 +q^2_+(x)χ_{\{u>0\}}(x) +q^2_-(x)χ_{\{u<0\}}(x) \end{equation*} where $q_\pm \in L^\infty(Ω)$. Almost minimizers do not satisfy a PDE or a monotonicity formula like minimizers do (see \cite{AC}, \cite{ACF}, \cite{CJK}, \cite{W}). Nevertheless we succeed in proving that they are locally Lipschitz, which is the optimal regularity for minimizers.

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Guy David, Tatiana Toro. 2013-06-12. Regularity for almost minimizers with free boundary. https://arxiv.org/abs/1306.2704

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