Full description of the eigenvalue set of the $(p,q)$-Laplacian with a Steklov-like boundary condition
Luminiţa Barbu, Gheorghe Moroşanu · arXiv (Cornell University) · 2020
In this paper we consider in a bounded domain $Ω\subset \mathbb{R}^N$ with smooth boundary an eigenvalue problem for the negative $(p,q)$-Laplacian with a Steklov-like boundary condition, where $p,\, q\in (1,\infty)$, $p eq q$, including the open case $p\in (1,\infty)$, $q\in (1, 2)$, $p eq q$. A full description of the set of eigenvalues of this problem is provided. Our results complement those previously obtained by Abreu and Madeira \cite{AM}, Barbu and Moroşanu \cite{BM}, Fărcăşeanu, Mihăilescu and Stancu-Dumitru \cite{FMS}, Mihăilescu \cite{MMih}, Mihăilescu and Moroşanu \cite{MM}.