Generalized eigenvector expansion for weakly perturbated discrete
operators
Milutin Dostanić
Abstract
In this paper we consider the expansion theorem in generalized
eigenvectors of the operator $A=L+T$, where $L$ is a discrete, positive
selfadjoint operator in a separable Hilbert space, and $T$ is a closed
operator which is subordinated to $L$ in a certain sense.