Existence of a degenerate singularity in the high activation energy limit of a reaction-diffusion equation

dc.creatorWeiss, G. S.
dc.creatorZhang, G.
dc.date2009-04-08
dc.date.accessioned2026-07-07T13:01:39Z
dc.date.available2026-07-07T13:01:39Z
dc.descriptionWe consider the singular perturbation problem $$ Δu_ε=β_ε(u_ε), $$ where $β_ε(s)=\frac{1}εβ(\frac{s}ε)$, $β$ is a Lipschitz continuous function such that $β>0$ in $(0, 1)$, $β\equiv 0$ outside $(0, 1)$ and $\int_0^1β(s) ds={1/2}$. We construct an example exhibiting a {\em degenerate singularity} as $ε_k\searrow 0$. More precisely, there is a sequence of solutions $u_{ε_k}\to u$ as $k\to \infty$, and there exists $x^0\in\partial\{u>0\}$ such that $$ \frac{u(x^0+r\cdot)}{r} \to 0 \textrm{as} r\to 0.$$ Known results suggest that this singularity must be {\em unstable}, which makes it hard to capture analytically and numerically. Our result answers a question raised by Jean-Michel Roquejoffre at the FBP'08 in Stockholm.
dc.description17 pages, 5 figures
dc.identifierhttps://arxiv.org/abs/0904.1261
dc.identifierhttp://arxiv.org/abs/0904.1261
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/226218
dc.subjectAnalysis of PDEs
dc.subject35R35; 35J60
dc.titleExistence of a degenerate singularity in the high activation energy limit of a reaction-diffusion equation
dc.typetext

Files

Collections