Remarks on the application of the Keldysh theorem to the completeness of root subspace of non-self-adjoint operators and comments on 'Spectral operators generated by Timoshenko beam model'

摘要

In this note, we show, by means of an example, that the assumption of compactness in the Keldysh theorem in proving the completeness of root subspaces of non-self-adjoint operators cannot be ignored. This indicates a gap of the above mentioned paper and many other related papers in the proof of completeness for the root subspaces of beam-related problems. (c) 2006 Elsevier B.V. All rights reserved.