Nonreal eigenvalues for second order differential operators on networks with circuits
This paper is devoted to studying problems of Sturm-Liouville type defined on different kind of domains, where finite networks which can be viewed as finite sets of thin beams or wires. These networks are usually identified as finite graphs, the wires are called edges and the nodes are called vertices. The authors show different behaviour of the networks. It is shown that the existence of nonreal eigenvalues of the corresponding differential operators implies that these operators cannot be selfadjoint with respect to any metric.
scientific article; zbMATH DE number 1866681
scientific article