Abstract

We prove some properties of the first eigenvalue for the elliptic system Δpu=λ|u|α|v|βv in Ω, Δqv=λ|u|α|v|βu in Ω, (u,v)W01,p(Ω)×W01,q(Ω). In particular, the first eigenvalue is shown to be simple. Moreover, the stability with respect to (p,q) is established.