4 citations · 15 across the 21 of their papers we have counts for
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On the similarity of boundary triples for dual pairs
Rytis Jursenas
The Weyl family of a dual pair of operators in a Krein space determines a minimal boundary triple uniquely up to similarity; if , a necessary and sufficient c…
On a boundary pair of a dissipative operator
Rytis Jursenas
The aim of this brief note is to demonstrate that the boundary pair of a dissipative operator is determined by the unitary boundary pair of its symmetric part.
On the similarity of boundary triples of symmetric operators in Krein spaces
Rytis Jursenas
It is a classical result that the Weyl function of a simple symmetric operator in a Hilbert space determines a boundary triple uniquely up to unitary equivalence. We generalize thi…
On necessary and sufficient conditions relating the adjoint of a column to a row of linear relations
Rytis Jursenas
A row and a column of two linear relations in Hilbert spaces are presented respectively as a sum and an intersection of two linear relations. As an application, necessary and suffi…
The A-model with mutually equal model parameters can lead to a Hilbert space model
Rytis Jursenas
It is known that the A-model for higher order singular perturbations can be considered as a Hilbert space model if the model parameters are mutually distinct, and that it is necess…
Weyl families of transformed boundary pairs
R. Jursenas
Let be an isometric boundary pair associated with a closed symmetric linear relation in a Krein space . Let be the Weyl family correspond…
On some extensions of the A-model
Rytis Jursenas
The A-model for finite rank singular perturbations of class , , is considered from the perspective of boundary…
Weyl families of essentially unitary pairs
Rytis Jursenas
It is known that the Weyl families corresponding to unitary boundary pairs belong to the class of Nevanlinna families. Here we…
The peak model for finite rank supersingular perturbations
Rytis Jursenas
In its original form the peak model for rank one supersingular perturbations of class or higher of a nonnegative self-adjoint operator requires that the Gram ma…