Large time behavior for a quasilinear diffusion equation with critical gradient absorption

Razvan Gabriel Iagar; Philippe Laurençot

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arXiv · 1503.07704

Large time behavior for a quasilinear diffusion equation with critical gradient absorption

Razvan Gabriel Iagar·Philippe Laurençot

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Abstract

We study the large time behavior of non-negative solutions to the nonlinear diffusion equation with critical gradient absorption $$\partial\_t u - \Delta\_{p}u + |\nabla u|^{q\_*} = 0 \quad \hbox{in} (0,\infty)\times\mathbb{R}^N\ ,$$ for $p\in(2,\infty)$ and $q\_*:=p-N/(N+1)$. We show that the asymptotic profile of compactly supported solutions is given by a source-type self-similar solution of the $p$-Laplacian equation with suitable logarithmic time and space scales. In the process, we also get optimal decay rates for compactly supported solutions and optimal expansion rates for their supports that strongly improve previous results.

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Razvan Gabriel Iagar, Philippe Laurençot. 2015-03-26. Large time behavior for a quasilinear diffusion equation with critical gradient absorption. https://arxiv.org/abs/1503.07704

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