## Found 25 Documents (Results 1–25)

### On the Kreĭn-von Neumann and Friedrichs extension of positive operators. (English)Zbl 07523179

de Snoo, H. S. V. (ed.) et al., Contributions to mathematics and statistics. Essays in honor of Seppo Hassi. Vaasa: University of Vaasa, School of Technology and Innovation. Acta Wasaensia 462, 165-178 (2021).
MSC:  47B25 47A20

### Completion and extension of operators in Kreĭn spaces. (English. Ukrainian original)Zbl 1370.47008

J. Math. Sci., New York 224, No. 4, 493-508 (2017); translation from Ukr. Mat. Visn. 13, No. 4, 452-472 (2016).
MSC:  47A20 46C20
Full Text:

Full Text:

Full Text:

### Characterization of eigenvalues in spectral gap for singular differential operators. (English)Zbl 1295.47044

MSC:  47E05 47B25
Full Text:

### M. Kreĭn’s research on semi-bounded operators, its contemporary developments, and applications. (English)Zbl 1201.47026

Adamyan, Vadim (ed.) et al., Modern analysis and applications. The Mark Krein centenary conference. Volume 1: Operator theory and related topics. Papers based on invited talks at the international conference on modern analysis and applications, Odessa, Ukraine, April 9–14, 2007. Basel: Birkhäuser (ISBN 978-3-7643-9918-4/v.1; 978-3-7643-9919-1/ebook; 978-3-7643-9924-5/set). Operator Theory: Advances and Applications 190, 65-112 (2009).
Full Text:

### Characterizations of positive selfadjoint extensions. (English)Zbl 1114.47009

MSC:  47A20 47B25 47A63
Full Text:

### $$Q$$-functions of quasi-selfadjoint contractions. (English)Zbl 1111.47016

Langer, Matthias (ed.) et al., Operator theory and indefinite inner product spaces. Presented on the occasion of the retirement of Heinz Langer in the colloquium on operator theory, Vienna, March 2004. Basel: Birkhäuser (ISBN 3-7643-7515-9/hbk). Operator Theory: Advances and Applications 163, 23-54 (2006).

### Inverse spectral theory for symmetric operators with several gaps: scalar-type Weyl functions. (English)Zbl 1083.47020

MSC:  47B25 47A10 47A56
Full Text:

Full Text:

### Selected works. II: Banach spaces and operator theory. (Избранные труды. II: Банаховы пространства и теория операторов.) (Russian)Zbl 0945.01014

Kyiv: Instytut Matematyky NAN Ukrainy. 348 p. (1996).
MSC:  01A75 46-03 47-03

### The shorted operator statistically interpreted. (English)Zbl 0744.62080

MSC:  62H05 47N30 62G99
Full Text:

### Description of some classes of extensions of a non-negative operator. (Russian. English summary)Zbl 0638.47002

Reviewer: J.S.Martin

### Commutative and normal extensions of Hermitian operators. (English. Russian original)Zbl 0638.47003

Sov. Math. 30, No. 12, 1-10 (1986); translation from Izv. Vyssh. Uchebn. Zaved., Mat. 1986, No. 12(295), 3-10 (1986).
Reviewer: Zhang Diang-Zhou

### Characteristic function and description of accretive and sectorial boundary problems for ordinary differential operators. (Russian. English summary)Zbl 0591.47035

Reviewer: V.Angelov
MSC:  47E05 47B44 34L99

### On sectorial extensions of positive Hermitian operators and their resolvents. (Russian)Zbl 0587.47009

Reviewer: A.Torgašev
MSC:  47A20 47B15

### Extensions and contractions of operators in a Banach space and their applications. (Russian)Zbl 0595.47004

Non-classical equations and equations of mixed type, Collect. sci. Works, Novosibirsk 1983, 3-26 (1983).
Reviewer: J.Danesova
MSC:  47A20

### Non-self-adjoint contractive extensions of a Hermitian contraction and theorems of Krein. (English)Zbl 0511.47005

MSC:  47A20 47B25 47A10
Full Text:

### Not self-adjoint contractive extension of a Hermitian contraction and theorems of M. G. Krejn. (Russian)Zbl 0492.47007

MSC:  47A20 47B25 47A10

### Friedrichs and Krein extensions of positive operators and holomorphic contraction semigroups. (English. Russian original)Zbl 0479.47023

Funct. Anal. Appl. 15, 308-309 (1982); translation from Funkts. Anal. Prilozh. 15, No. 4, 91-92 (1981).
MSC:  47B25 47B44 47D03
Full Text:

### The Birman-Krein-Vishik theory of self-adjoint extensions of semibounded operators. (English)Zbl 0467.47017

MSC:  47B25 34L99

### Point spectrum of semibounded operator extensions. (English)Zbl 0438.47026

Prepr. Ser., Aarhus Univ. 1979/80, No. 21-31, 8 p. (1980).
MSC:  47B25 47A10

MSC:  34B99

### On $$Q$$-functions and SC-resolvents of nondensely defined Hermitian contractions. (Über $$Q$$-Funktionen und SC-Resolventen nicht kompakt gegebener Hermitescher Kontraktionen.) (Russian)Zbl 0384.47006

Reviewer: T. Ando
MSC:  47A20 47A10

Full Text:

all top 5

all top 3