Multipliers for eigenfunction expansions of some Schrödinger operators

Eigenfunction Expansions for Some Nonselfadjoint Operators and the Transport Equation*

There are many papers dealing with various aspects of the perturbation theory of a continuous spectrum [l-5, 12-151. In [3-51 some problems with nonselfadjoint operators were considered. In [3b] conditions for the perturbed operator to be similar to the unperturbed one are given. In [4] the Schrijdinger operator with a complex-valued potential was considered. In [S ] a theorem is announced in w...

Eigenfunction Expansions for Schrödinger Operators on Metric Graphs

We construct an expansion in generalized eigenfunctions for Schrödinger operators on metric graphs. We require rather minimal assumptions concerning the graph structure and the boundary conditions at the vertices.

Perturbation of eigenfunction expansions.

some properties of fuzzy hilbert spaces and norm of operators

in this thesis, at first we investigate the bounded inverse theorem on fuzzy normed linear spaces and study the set of all compact operators on these spaces. then we introduce the notions of fuzzy boundedness and investigate a new norm operators and the relationship between continuity and boundedness. and, we show that the space of all fuzzy bounded operators is complete. finally, we define...

Convergence of Generalized Eigenfunction Expansions

We present a simplified theory of generalized eigenfunction expansions for a commuting family of bounded operators and with finitely many unbounded operators. We also study the convergence of these expansions, giving an abstract type of uniform convergence result, and illustrate the theory by giving two examples: The Fourier transform on Hecke operators, and the Laplacian operators in hyperboli...