14 citations · 17 across the 16 of their papers we have counts for
18 papers
Operators without eigenvalues in finite-dimensional vector spaces: Linearization and Spectral Equivalence
Branko Ćurgus, Aad Dijksma
In this paper is a closed symmetric linear relation in a Krein space with adjoint , finite and equal defect numbers , and a boundary mapping $\mathsf{b}:…
Floor, ceiling and the space between
Árpád Bényi, Branko Ćurgus
Motivated by questions on the ranges of commutators of dilated floor functions and one posed in Problem 27327 from Gazeta Matematică, we investigate the precise ranges of certain g…
Indefinite Sturm-Liouville operators in polar form
Branko Ćurgus, Volodymyr Derkach, Carsten Trunk
We consider the indefinite Sturm-Liouville differential expression \[\mathfrak{a}(f) := - \frac{1}{w}\left( \frac{1}{r} f' \right)',\] where is defined on a finite o…
Partially fundamentally reducible operators in Krein spaces
Branko Ćurgus, Vladimir Derkach
A self-adjoint operator in a Krein space is called partially fundamentally reducible if there exist a fundamental decomposition $…
The Riesz basis property of an indefinite Sturm-Liouville problem with non-separated boundary conditions
Branko Ćurgus, Andreas Fleige, Aleksey Kostenko
We consider a regular indefinite Sturm-Liouville eigenvalue problem \{} on subject to general self-adjoint boundary conditions and with a weight function…
Outer median triangles
Árpád Bényi, Branko Ćurgus
We define the notions of outer medians and outer median triangles. We show that outer median triangles enjoy similar properties to that of the median triangle.