27 citations · 113 across the 31 of their papers we have counts for
5 papers · 1 filter
Zero measure Cantor spectra for continuum one-dimensional quasicrystals
Daniel Lenz, Christian Seifert, Peter Stollmann
We study Schrödinger operators on with measures as potentials. Choosing a suitable subset of measures we can work with a dynamical system consisting of measures. We then relat…
Boundary systems and (skew-)self-adjoint operators on infinite metric graphs
Carsten Schubert, Christian Seifert, Jürgen Voigt +1
We generalize the notion of Lagrangian subspaces to self-orthogonal subspaces with respect to a (skew-)symmetric form, thus characterizing (skew-)self-adjoint and unitary operators…
On the perturbation of positive semigroups
Christian Seifert, Daniel Wingert
We prove a perturbation result for positive semigroups, thereby extending a heat kernel estimate by Barlow, Grigor'yan and Kumagai for Dirichlet forms (\cite{bgk2009}) to positive…
A weak Gordon type condition for absence of eigenvalues of one-dimensional Schrödinger operators
Christian Seifert, Hendrik Vogt
We study one-dimensional Schrödinger operators with complex measures as potentials and present an improved criterion for absence of eigenvalues which involves a weak local periodic…
Absence of absolutely continuous spectrum for the Kirchhoff Laplacian on radial trees
Pavel Exner, Christian Seifert, Peter Stollmann
In this paper we prove that the existence of absolutely continuous spectrum of the Kirchhoff Laplacian on a radial metric tree graph together with a finite complexity of the geomet…