Left-definite variations of the classical Fourier expansion theorem.
Maximal invariant neutral subspaces and an application to the algebraic Riccati equation.
Maximal Monotonicity of Operators with Sufficiently Large Domain and Application to the Hartree Problem.
Note to the paper by R. Hempel, A. M. Hinz, and H. Kalf: On the Essential Spectrum of Schrödinger Operators with Spherically Symmetric Potentials.
Notes on q-deformed operators
The paper concerns operators of deformed structure like q-normal and q-hyponormal operators with the deformation parameter q being a positive number different from 1. In particular, an example of a q-hyponormal operator with empty spectrum is given, and q-hyponormality is characterized in terms of some operator inequalities.
On a theorem of Jörgens and Chernoff concerning essential self-adjointness of Dirac operators.
On Commuting Unbounded Self-Adjoint Operators. III.
On where has infinitely many “bumps”
On determination of eigenvalues and eigenvectors of selfadjoint operators
Two simple methods for approximate determination of eigenvalues and eigenvectors of linear self-adjoint operators are considered in the following two cases: (i) lower-upper bound of the spectrum of is an isolated point of ; (ii) (not necessarily an isolated point of with finite multiplicity) is an eigenvalue of .
On eigenfunction expansions and scattering theory.
On Essential Self-Adjointness for Singular Elliptic Differential Operators.
On essential selfadjointness of the Weyl quantized relativistic Hamiltonian.
On Jensen's inequality for self-adjoint operators in Hilbert space
On -accretive Schrödinger-type operators with singular potentials on manifolds of bounded geometry.
On -sectorial Schrödinger-type operators with singular potentials on manifolds of bounded geometry
We consider a Schrödinger-type differential expression , where is a -bounded Hermitian connection on a Hermitian vector bundle of bounded geometry over a manifold of bounded geometry with metric and positive -bounded measure , and is a locally integrable section of the bundle of endomorphisms of . We give a sufficient condition for -sectoriality of a realization of in . In the proof we use generalized Kato’s inequality as well as a result on the positivity of satisfying the...
On Non-Degeneracy of the Ground State of Schrödinger Operators.
On Optimal Spectral Estimator for Multi-Dimensional Time Series with an Infinite Number of Sample Points.
On the Canonical Commutation Relations.
On the Essential Spectrum of Schrödinger Operators with Spherically Symmetric Potentials.
On the Existence of Minimal Operators for Schrödinger-Type Differential Expressions.