Eigenvalues of two parameter polynomial operator pencils of waveguide type
This paper deals with the study of the spectral structure of two parameter unbounded operator pencils of waveguide type. Problems of this type arise in the analysis of some classes of differential operators. There are established several properties on energetic stability and variational principles associated to the real eigenvalues. Connections between the energetic stability and a related perturbation problem are also developed in the present paper.
scientific article; zbMATH DE number 5117987