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arXiv · 2106.04135

Regularity of the free boundary for a parabolic cooperative system

Gohar Aleksanyan·Morteza Fotouhi·Henrik Shahgholian·Georg S. Weiss
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Abstract

In this paper we study the following parabolic system \begin{equation*} \Delta \u -\partial_t \u =|\u|^{q-1}\u\,\chi_{\{ |\u|>0 \}}, \qquad \u = (u^1, \cdots , u^m) \ , \end{equation*} with free boundary $\partial \{|\u | >0\}$. For $0\leq q<1$, we prove optimal growth rate for solutions $\u $ to the above system near free boundary points, and show that in a uniform neighbourhood of any a priori well-behaved free boundary point the free boundary is $C^{1, \alpha}$ in space directions and half-Lipschitz in the time direction.

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Gohar Aleksanyan, Morteza Fotouhi, Henrik Shahgholian, Georg S. Weiss. 2021-06-08. Regularity of the free boundary for a parabolic cooperative system. https://arxiv.org/abs/2106.04135

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