On contractions in Hilbert space

In the first part of the paper we study the decompositions of a (bounded linear) operator similar to a normal operator in Hilbert space into the orthogonal sum of a normal (self-adjoint, unitary) part and of a part free of the given property, respectively. In the second part we investigate in a fini...

Teljes leírás

Elmentve itt :
Bibliográfiai részletek
Szerző: Nagy Béla
További közreműködők: Kérchy László
Dokumentumtípus: Cikk
Megjelent: Bolyai Institute, University of Szeged Szeged 2013
Sorozat:Acta scientiarum mathematicarum 79 No. 1-2
Kulcsszavak:Matematika, Hilbert-tér
Tárgyszavak:
Online Access:http://acta.bibl.u-szeged.hu/30872
Leíró adatok
Tartalmi kivonat:In the first part of the paper we study the decompositions of a (bounded linear) operator similar to a normal operator in Hilbert space into the orthogonal sum of a normal (self-adjoint, unitary) part and of a part free of the given property, respectively. In the second part we investigate in a finite dimensional Hilbert space the minimal unitary power dilations (till the exponent k) of a contraction. We determine the general form of such dilations, examine their spectra, and the question of their isomorphy. The first step of the study here is also the decomposition of the contraction into unitary and completely non-unitary parts.
Terjedelem/Fizikai jellemzők:235-251
ISSN:0001-6969