Universality of weighted composition operators on L2 ([0,1]) and Sobolev spaces

It is shown that a class of composition operators C$ has the property that for every A in the interior of the spectrum of C$ the operator U = Cj, — Aid is universal in the sense of Caradus, i.e., every Hilbert space operator has a non-zero multiple similar to the restriction of U to an invariant sub...

Teljes leírás

Elmentve itt :
Bibliográfiai részletek
Szerző: Pozzi Elodie
Dokumentumtípus: Cikk
Megjelent: Bolyai Institute, University of Szeged Szeged 2012
Sorozat:Acta scientiarum mathematicarum 78 No. 3-4
Kulcsszavak:Matematika, Szoboljev-tér, Operátorelmélet
Tárgyszavak:
Online Access:http://acta.bibl.u-szeged.hu/16452
Leíró adatok
Tartalmi kivonat:It is shown that a class of composition operators C$ has the property that for every A in the interior of the spectrum of C$ the operator U = Cj, — Aid is universal in the sense of Caradus, i.e., every Hilbert space operator has a non-zero multiple similar to the restriction of U to an invariant subspace. As a generalization, weighted composition operators on the L2 and Sobolev spaces of the unit interval are shown to have the same property and thus a complete knowledge of their minimal invariant subspaces would imply a solution to the invariant subspace problem for Hilbert space. Moreover, a generalization of sufficient conditions for an operator to be universal is obtained. Cyclicity and non-cyclicity results for a certain class of weights and composition functions are also proved.
Terjedelem/Fizikai jellemzők:609-642
ISSN:0001-6969