## Advances in Differential Equations

- Adv. Differential Equations
- Volume 6, Number 8 (2001), 931-958.

### The effect of geometry of the domain boundary in an elliptic Neumann problem

Daomin Cao and Ezzat S. Noussair

#### Abstract

In this paper we consider the problem $$ \begin{cases} -\Delta u + \mu u= u^{2^* -1 -{\varepsilon}} \quad \hbox{in } \Omega \\ u>0 \quad \hbox{in } \Omega \ \quad \frac{\partial u}{\partial \nu} =0 \quad \hbox{on } \partial \Omega \end{cases} $$ where $\Omega$ is a bounded, smooth domain in ${\mathbb R}^N (N\geq 3),\ 2^* = \frac{2N}{N-2}, \ \mu>0, \ {\varepsilon} \in [0, \frac{4}{N-2})$, $\nu$ is the unit outward normal vector to $\partial \Omega$. We show the topological effect of superlevel and/or sublevel sets of the function of mean curvature of $\partial \Omega$ on the number of one- or multipeak positive solutions as ${\varepsilon} \to 0$ for fixed $\mu$ and $\mu \to +\infty$ for ${\varepsilon} =0$. The solutions obtained concentrate at some boundary points with negative mean curvature (for ${\varepsilon}>0 $ small) or positive mean curvature (for ${\varepsilon}=0, \ \mu$ large).

#### Article information

**Source**

Adv. Differential Equations Volume 6, Number 8 (2001), 931-958.

**Dates**

First available in Project Euclid: 2 January 2013

**Permanent link to this document**

https://projecteuclid.org/euclid.ade/1357140553

**Mathematical Reviews number (MathSciNet)**

MR1828499

**Zentralblatt MATH identifier**

1140.35411

**Subjects**

Primary: 35J60: Nonlinear elliptic equations

Secondary: 35B40: Asymptotic behavior of solutions 35B45: A priori estimates

#### Citation

Cao, Daomin; Noussair, Ezzat S. The effect of geometry of the domain boundary in an elliptic Neumann problem. Adv. Differential Equations 6 (2001), no. 8, 931--958. https://projecteuclid.org/euclid.ade/1357140553