An elliptic boundary problem involving an indefinite weight
M. Faierman · Proceedings of the Royal Society of Edinburgh Section A Mathematics · 2000
The spectral theory for non-self-adjoint elliptic boundary problems involving an indefinite weight function has only been established for the case of higher-order operators under the assumption that the reciprocal of the weight function is essentially bounded. In this paper we are concerned with the spectral theory for a case where the weight function vanishes on a set of positive measure.