8 citations · 25 across the 12 of their papers we have counts for
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Nonrelativistic Limit of Generalized MIT Bag Models and Spectral Inequalities
Jussi Behrndt, Dale Frymark, Markus Holzmann +1
For a family of self-adjoint Dirac operators subject to generalized MIT bag boundary conditions on domains in it is shown that…
Spectral analysis of the Dirac operator with a singular interaction on a broken line
Dale Frymark, Markus Holzmann, Vladimir Lotoreichik
We consider the one-parametric family of self-adjoint realizations of the two-dimensional massive Dirac operator with a Lorentz scalar -shell interaction of strength $τ\in\mathb…
Spectral Properties of Singular Sturm-Liouville Operators via Boundary Triples and Perturbation Theory
Dale Frymark, Constanze Liaw
We apply both the theory of boundary triples and perturbation theory to the setting of semi-bounded Sturm-Liouville operators with two limit-circle endpoints. For general boundary…
The Spectrum of Self-Adjoint Extensions associated with Exceptional Laguerre Differential Expressions
Dale Frymark, Jessica Stewart Kelly
Exceptional Laguerre-type differential expressions make up an infinite class of Schrödinger operators having rational potentials and one limit-circle endpoint. In this manuscript,…
Self-adjointness of the 2D Dirac operator with singular interactions supported on star-graphs
Dale Frymark, Vladimir Lotoreichik
We consider the two-dimensional Dirac operator with Lorentz-scalar -shell interactions on each edge of a star-graph. An orthogonal decomposition is performed which shows such an…
Singular Boundary Conditions for Sturm--Liouville Operators via Perturbation Theory
Michael Bush, Dale Frymark, Constanze Liaw
We show that all self-adjoint extensions of semi-bounded Sturm--Liouville operators with general limit-circle endpoint(s) can be obtained via an additive singular form bounded self…
Spectral Analysis, Model Theory and Applications of Finite-Rank Perturbations
Dale Frymark, Constanze Liaw
This survey focuses on two main types of finite-rank perturbations: self-adjoint and unitary. We describe both classical and more recent spectral results. We pay special attention…
Spectral Analysis of Iterated Rank-One Perturbations
Dale Frymark, Constanze Liaw
The authors study the spectral theory of self-adjoint operators that are subject to certain types of perturbations. An iterative introduction of infinitely many randomly coupled ra…