On critical $p$-Laplacian systems (1508.06006v1)
Abstract: We consider the critical $p$-Laplacian system \begin{equation}\label{92} \begin{cases}-\Delta_p u-\frac{\lambda a}{p}|u|{a-2}u|v|b =\mu_1|u|{p\ast-2}u+\frac{\alpha\gamma}{p\ast}|u|{\alpha-2}u|v|{\beta}, &x\in\Omega,\ -\Delta_p v-\frac{\lambda b}{p}|u|a|v|{b-2}v =\mu_2|v|{p\ast-2}v+\frac{\beta\gamma}{p\ast}|u|{\alpha}|v|{\beta-2}v, &x\in\Omega,\ u,v\ \text{in } D_0{1,p}(\Omega), \end{cases} \end{equation} where $\Delta_p:=\text{div}(|\nabla u|{p-2}\nabla u)$ is the $p$-Laplacian operator defined on $D{1,p}(\mathbb{R}N):={u\in L{p\ast}(\mathbb{R}N):|\nabla u|\in Lp(\mathbb{R}N)}$, endowed with norm $|u|{D{1,p}}:=\big(\int{\mathbb{R}N}|\nabla u|p\text{d}x\big){\frac{1}{p}}$, $N\ge3$, $1<p<N$, $\lambda, \mu_1, \mu_2\ge 0$, $\gamma\neq0$, $a, b, \alpha, \beta > 1$ satisfy $a + b = p, \alpha + \beta = p\ast:=\frac{Np}{N-p}$, the critical Sobolev exponent, $\Omega$ is $\mathbb{R}N$ or a bounded domain in $\mathbb{R}N$, $D_0{1,p}(\Omega)$ is the closure of $C_0\infty(\Omega)$ in $D{1,p}(\mathbb{R}N)$. Under suitable assumptions, we establish the existence and nonexistence of a positive least energy solution. We also consider the existence and multiplicity of nontrivial nonnegative solutions.