Article
Keywords:
continuum spectrum; extremal solution; boundary reaction
Summary:
We study the semilinear problem with the boundary reaction \[ -\Delta u + u = 0 \quad \text {in} \ \Omega , \qquad \frac {\partial u}{\partial \nu } = \lambda f(u) \quad \text {on} \ \partial \Omega , \] where $\Omega \subset \mathbb {R}^N$, $N \ge 2$, is a smooth bounded domain, $f\colon [0, \infty ) \to (0, \infty )$ is a smooth, strictly positive, convex, increasing function which is superlinear at $\infty $, and $\lambda >0$ is a parameter. It is known that there exists an extremal parameter $\lambda ^* > 0$ such that a classical minimal solution exists for $\lambda < \lambda ^*$, and there is no solution for $\lambda > \lambda ^*$. Moreover, there is a unique weak solution $u^*$ corresponding to the parameter $\lambda = \lambda ^*$. In this paper, we continue to study the spectral properties of $u^*$ and show a phenomenon of continuum spectrum for the corresponding linearized eigenvalue problem.
References:
[1] Brezis, H., Cazenave, T., Martel, Y., Ramiandrisoa, A.:
Blow up for $u_t - \Delta u = g(u)$ revisited. Adv. Differ. Equ. 1 73-90 (1996).
MR 1357955
[2] Brezis, H., Vázquez, J. L.:
Blow-up solutions of some nonlinear elliptic problems. Rev. Mat. Univ. Complutense Madr. 10 443-469 (1997).
MR 1605678 |
Zbl 0894.35038
[4] Chipot, M., Shafrir, I., Fila, M.:
On the solutions to some elliptic equations with nonlinear Neumann boundary conditions. Adv. Differ. Equ. 1 91-110 (1996).
MR 1357956 |
Zbl 0839.35042
[5] Dávila, J.:
Singular solutions of semi-linear elliptic problems. Handbook of Differential Equations: Stationary Partial Differential Equations Elsevier, Amsterdam 83-176 (2008).
MR 2569324 |
Zbl 1191.35131
[7] Dupaigne, L.:
Stable Solutions of Elliptic Partial Differential Equations. Chapman & Hall Monographs and Surveys in Pure and Applied Mathematics 143 CRC Press, Boca Raton (2011).
MR 2779463 |
Zbl 1228.35004
[8] Martel, Y.:
Uniqueness of weak extremal solutions of nonlinear elliptic problems. Houston J. Math. 23 161-168 (1997).
MR 1688823 |
Zbl 0884.35037
[10] Takahashi, F.:
Extremal solutions to Liouville-Gelfand type elliptic problems with nonlinear Neumann boundary conditions. Commun. Contemp. Math. 27 pages, DOI:10.1142/S0219199714500163 (2014).
DOI 10.1142/S0219199714500163 |
MR 3325039