Eigenfunction expansions and scattering theory for Dirac operators

Eigenfunction Expansions and Transformation Theory

Generalized eigenfunctions may be regarded as vectors of a basis in a particular direct integral of Hilbert spaces or as elements of the antidual space Φ× in a convenient Gelfand triplet Φ ⊆ H ⊆ Φ×. This work presents a fit treatment for computational purposes of transformations formulas relating different generalized bases of eigenfunctions in both frameworks direct integrals and Gelfand tripl...

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.

q-Sturm-Liouville theory and the corresponding eigenfunction expansions

The aim of this paper is to study the q-Schrödinger operator L = q(x) −∆q, where q(x) is a given function of x defined over R q = {qn, n ∈ Z} and ∆q is the q-Laplace operator ∆qf(x) = 1 x [ f(qx)− 1 + q q f(x) + 1 q f(qx) ]

Perturbation of eigenfunction expansions.