The Fujita Exponent for Semilinear Heat Equations with Quadratically Decaying Potential or in an Exterior Domain

dc.creatorPinsky, Ross G.
dc.date2008-05-09
dc.date2008-05-13
dc.date.accessioned2026-07-07T09:38:11Z
dc.date.available2026-07-07T09:38:11Z
dc.descriptionConsider the equation u_t=Δu-Vu +au^p \text{in} R^n\times (0,T); u(x,0)=ϕ(x)\gneq0, \text{in} R^n, where $p>1$, $n\ge2$, $T\in(0,\infty]$, $V(x)\sim\fracω{|x|^2}$ as $|x|\to\infty$, for some $ω\neq0$, and $a(x)$ is on the order $|x|^m$ as $|x|\to\infty$, for some $m\in (-\infty,\infty)$. A solution to the above equation is called global if $T=\infty$. Under some additional technical conditions, we calculate a critical exponent $p^*$ such that global solutions exist for $p>p^*$, while for $1<p\le p^*$, all solutions blow up in finite time. We also show that when $V\equiv0$, the blow-up/global solution dichotomy for \eqref{abstract} coincides with that for the corresponding problem in an exterior domain with the Dirichlet boundary condition, including the case in which $p$ is equal to the critical exponent.
dc.description24 pages, replaces and improves previous version
dc.identifierhttps://arxiv.org/abs/0805.1313
dc.identifierhttp://arxiv.org/abs/0805.1313
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/160717
dc.subjectAnalysis of PDEs
dc.subject35K55, 35B33
dc.titleThe Fujita Exponent for Semilinear Heat Equations with Quadratically Decaying Potential or in an Exterior Domain
dc.typetext

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