This issuePrevious ArticleA note on coupled nonlinear Schrödinger systems under the effect of general nonlinearitiesNext ArticleArbitrarily many solutions for an elliptic Neumann problem with sub- or supercritical
nonlinearity
Estimates for extremal values of $-\Delta u=
h(x) u^{q}+\lambda W(x) u^{p}$
In this paper we provide uniform estimates for $\lambda^{*}(N,
\Omega, q, p, h, W)$ of nonlinear elliptic equations $-\Delta u=
h(x) u^{q}+\lambda W(x) u^{p}$ where $W$ may change sign. We use a
variational technique. Still few general results are known for
this type of estimates except [6] of Gazzola and Malchiodi,
which provide uniform estimates for the extremal value in case
$-\Delta u=\lambda (1+u)^{p}$.