Special Session 101: 

Multiplicity of positive solutions for elliptic equations arising in a theory of thermal explosion

Eunkyung Ko
Keimyung University
Korea
Co-Author(s):    
Abstract:
In this talk we consider a mathematical model of thermal explosion which is described by the boundary value problem $$\,\,\,\,\,\,\,\,\,\,\,\,\left\{ \begin{array}{rlll} -div(|\nabla u|^{N-2}\nabla u) &=&\lambda e^{u^\alpha}, & x \in\Omega,\\ \\ |\nabla u|^{N-2}\frac{\partial u}{\partial \nu}+g(u) &=&0, & x \in \partial\Omega, \end{array}\right. $$ where $\Omega$ is a bounded domain in $ \mathbb{R}^N, N\geq 2,$ $\partial \Omega$ is the smooth boundary of $\Omega$ with outward normal $\nu,$ $\alpha \in (0, \frac{N}{N-1}]$ and $\lambda$ is a positive parameter. Using variational methods we show that there exists $0< \Lambda < \infty$ such that the problem has at least two positive solutions if $0 < \lambda < \Lambda,$ no solution if $\lambda > \Lambda$ and at least one positive solution when $\lambda =\Lambda.$