Characteristic function of M. S. Livšic and triangular models of bounded linear operators

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Dubovoy, Vladimir K., Kirstein, Bernd, Mädler, Conrad, Müller, Karsten
Format: Preprint
Veröffentlicht: 2023
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913181034610688
author Dubovoy, Vladimir K.
Kirstein, Bernd
Mädler, Conrad
Müller, Karsten
author_facet Dubovoy, Vladimir K.
Kirstein, Bernd
Mädler, Conrad
Müller, Karsten
contents This paper is dedicated to the introduction in a circle of ideas and methods, which are connected with the notion of characteristic function of a non-selfadjoint operator. We start with the consideration of closed and open systems (Subsections 2.1.1-2.1.2). In Subsections 2.1.2-2.1.3 we introduce the notion of operator colligation and define the characteristic function of the operator colligation as transfer function of the corresponding open system. In Section 3 we state three basic properties of the c.o.f.. First (Subsection 3.1), we note that the c.o.f. is the full unitary invariant of the operator colligation. Second (see Theorem 3.4), it turns out that the invariant subspaces of the corresponding operator are associated with left divisors of the c.o.f.. Third, the $J$-property of the c.o.f. (see (3.6)-(3.8)) is a basic property which determines the class of c. o. f. (see Section 4). In Chapter 4 we describe the classes of characteristic functions which play an important role in our considerations. In Chapter 5 we state necessary facts on multiplicative integral. Chapter 6 is devoted to the factorization theorem (Theorem 6.7) for matrix-valued characteristic function. In Chapter 7 we construct a triangular Livšic model of bounded linear operator and as application we obtain some known results on dissipative operators.
format Preprint
id arxiv_https___arxiv_org_abs_2312_17333
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Characteristic function of M. S. Livšic and triangular models of bounded linear operators
Dubovoy, Vladimir K.
Kirstein, Bernd
Mädler, Conrad
Müller, Karsten
Complex Variables
Mathematical Physics
Analysis of PDEs
Spectral Theory
47B28, 47A45, 47A40, 47A56
This paper is dedicated to the introduction in a circle of ideas and methods, which are connected with the notion of characteristic function of a non-selfadjoint operator. We start with the consideration of closed and open systems (Subsections 2.1.1-2.1.2). In Subsections 2.1.2-2.1.3 we introduce the notion of operator colligation and define the characteristic function of the operator colligation as transfer function of the corresponding open system. In Section 3 we state three basic properties of the c.o.f.. First (Subsection 3.1), we note that the c.o.f. is the full unitary invariant of the operator colligation. Second (see Theorem 3.4), it turns out that the invariant subspaces of the corresponding operator are associated with left divisors of the c.o.f.. Third, the $J$-property of the c.o.f. (see (3.6)-(3.8)) is a basic property which determines the class of c. o. f. (see Section 4). In Chapter 4 we describe the classes of characteristic functions which play an important role in our considerations. In Chapter 5 we state necessary facts on multiplicative integral. Chapter 6 is devoted to the factorization theorem (Theorem 6.7) for matrix-valued characteristic function. In Chapter 7 we construct a triangular Livšic model of bounded linear operator and as application we obtain some known results on dissipative operators.
title Characteristic function of M. S. Livšic and triangular models of bounded linear operators
topic Complex Variables
Mathematical Physics
Analysis of PDEs
Spectral Theory
47B28, 47A45, 47A40, 47A56
url https://arxiv.org/abs/2312.17333