1 citations · 1 across the 8 of their papers we have counts for
9 papers
Dissipation and c-Entropy in Nevanlinna-Pick Interpolation
Sergey Belyi, Konstantin A. Makarov, Eduard Tsekanovskii
We study interpolation L-systems realizing finite Nevanlinna-Pick data sets and analyze their structural and quantitative characteristics. Explicit formulas are derived for the c-e…
Threshold Virtual States of a Jacobi operator
Saidakhmat N. Lakaev, Konstantin A. Makarov
We prove that the set of parameters for which a virtual level appears at the edge of the continuous spectrum of a Jacobi matrix with a finite-rank diagonal perturbation constitutes…
The c-Entropy of non-dissipative L-systems
Sergey Belyi, Konstantin A. Makarov, Eduard Tsekanovskii
In this paper, we extend the definition of c-entropy to canonical L-systems with non-dissipative state-space operators. We also introduce the concepts of dissipation and accumulati…
L-systems with Multiplication Operator and c-Entropy
Sergey Belyi, Konstantin Makarov, Eduard Tsekanovskii
In this note, we utilize the concepts of c-entropy and the dissipation coefficient in connection with canonical L-systems based on the multiplication (by a scalar) operator. Additi…
The c-Entropy optimality of Donoghue classes
Sergey Belyi, Konstantin Makarov, Eduard Tsekanovskii
In this note we evaluate c-Entropy of perturbed L-systems introduced in [5]. Explicit formulas relating the c-Entropy of the L-systems and the perturbation parameter are establishe…
On the c-entropy of L-systems with Schrodinger operator
Sergey Belyi, Konstantin Makarov, Eduard Tsekanovskii
We study L-systems whose main operators are extensions of one-dimensional half-line Schrödinger operators with deficiency indices , the Schrödinger L-systems. Introducing n…
A system coupling and Donoghue classes of Herglotz-Nevanlinna functions
Sergey Belyi, Konstantin Makarov, Eduard Tsekanovskii
We study the impedance functions of conservative L-systems with the unbounded main operators. In addition to the generalized Donoghue class $\sM_κ$ of Herglotz-Nevanlinna functions…
On dissipative and non-unitary solutions to operator commutation relations
K. A. Makarov, E. Tsekanovskii
We study the (generalized) semi-Weyl commutation relations $$ U_gAU_g^*=g(A) \quad \text{ on }\quad \Dom(A), $$ where is a densely defined operator and is a…
The addition and multiplication theorems
K. A. Makarov, E. Tsekanovskii
We discuss the classes $\fC$, $\fM$, and $\fS$ of analytic functions that can be realized as the Livšic characteristic functions of a symmetric densely defined operator wi…