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arXiv · 2007.10838

Solutions of super-linear elliptic equations and their Morse indices

Foued Mtiri
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Abstract

We investigate here the degenerate bi-harmonic equation: $$Δ_{m}^2 u=f(x,u)\; \;\;\mbox{in} Ø,\quad u = Δu = 0\quad \mbox{on }\; \pΩ,$$ with $m\ge 2,$ and also the degenerate tri-harmonic equation: $$ -Δ_{m}^3 u=f(x,u)\;\;\; \mbox{in} Ø,\quad u = \frac{\p u}{\p ν} = \frac{\p^{2} u}{\pν^{2}} = 0\quad \mbox{on }\; \pΩ,$$ where $Ω\subset \mathbb{R}^{N}$ is a bounded domain with smooth boundary $N>4$ or $N>6$ resp, and $f \in \mathrm{C}^{1}(Ω\times \mathbb{R})$ satisfying suitable m-superlinear and subcritical growth conditions. Our main purpose is to establish $L^{p}$ and $L^{\infty}$ explicit bounds for weak solutions via the Morse index. Our results extend previous explicit estimate obtained in \cite{c, HHF, hyf, lec}.

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Foued Mtiri. 2020-07-20. Solutions of super-linear elliptic equations and their Morse indices. https://arxiv.org/abs/2007.10838

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