Spectral analysis of perturbed multiplication operators occurring in polymerization chemistry

On Similarity of Perturbed Multiplication Operators

Let S be the multiplication operator by an independent variable x in L2(0, 1) and V be an integral operator of Volterra type. We find conditions for T := S + V to be similar to S and discuss some generalisations of the results obtained to an abstract setting.

Spectral Approximation of Multiplication Operators

A linear operator on a Hilbert space may be approximated with nite matrices by choosing an orthonormal basis of the Hilbert space. For an operator that is not compact such approximations cannot converge in the norm topology on the space of operators. Multiplication operators on spaces of L2 functions are never compact; for them we consider how well the eigenvalues of the matrices approximate th...

Composition Operators and Multiplication Operators on Orlicz Spaces

This article has no abstract.

Remarks on the inverse spectral theory for singularly perturbed operators

Let A be an unbounded from above self-adjoint operator in a separable Hilbert space H and EA(·) its spectral measure. We discuss the inverse spectral problem for singular perturbations à of A (à and A coincide on a dense set in H). We show that for any a ∈ R there exists a singular perturbation à of A such that à and A coincide in the subspace EA((−∞, a))H and simultaneously à has an additional...

On Inverse Spectral Theory for Singularly Perturbed Operators: Point Spectrum