Electronic Journal of Differential Equations (Apr 2016)
Multiple solutions for critical elliptic problems with fractional Laplacian
Abstract
This article is devoted to the study of the nonlocal fractional equation involving critical nonlinearities $$\displaylines{ (-\Delta)^{\alpha/2} u=\lambda u+|u|^{2^{\ast}_{\alpha}-2}u \quad \text{in } \Omega,\cr u=0 \quad \text{on } \partial \Omega, }$$ where $\Omega$ is a smooth bounded domain of $\mathbb{R}^N$, $N \geq 2\alpha$, $\alpha\in(0,2)$, $\lambda\in(0,\lambda_{1})$ and $2^*_{\alpha}=\frac{2N}{N-\alpha}$ is critical exponent. We show the existence of at least $\hbox{cat}_{\Omega}(\Omega) $ nontrivial solutions for this problem.