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arXiv · 1611.05488

On the regularity and partial regularity of extremal solutions of a Lane-Emden system

Hatem Hajlaoui
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Abstract

In this paper, we consider the system $-Δu =λ(v+1)^p,\;\;-Δv = γ(u+1)^θ$ on a smooth bounded domain $Ω$ in $\mathbb{R}^N$ with the Dirichlet boundary condition $u=v=0$ on $\partial Ω.$ Here $ λ,γ$ are positive parameters. Let $x_0$ be the largest root of the polynomial \begin{equation*} H(x) = x^4 - \frac{16pθ(p+1)(θ+1)}{(pθ-1)^2}x^2 + \frac{16pθ(p+1)(θ+1)(p+θ+2)}{(pθ-1)^3}x -\frac{16pθ(p+1)^2(θ+1)^2}{(pθ-1)^4}. \end{equation*} We show that the extremal solutions associated to the above system are bounded provided $N<2+2x_0.$ This improves the previous work in \cite{co1}. We also prove that, if $N\geq 2+2x_0,$ then the singular set of any extremal solution has Hausdorff dimension less or equal to $N-(2+2x_0).$

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Hatem Hajlaoui. 2016-11-16. On the regularity and partial regularity of extremal solutions of a Lane-Emden system. https://arxiv.org/abs/1611.05488

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