A nonhypercyclic operator with orbit-density properties

In this note we construct an operator T on a (separable, complex) Hilbert space such that for every nonzero vector x, the sequence {||Tnx||}ngN is dense in R+, but despite this, T is not hypercyclic (i.e., no vector in H has a dense orbit). In addition, this operator has the property that there are...

Teljes leírás

Elmentve itt :
Bibliográfiai részletek
Szerző: Smith Lidia
Dokumentumtípus: Cikk
Megjelent: Bolyai Institute, University of Szeged Szeged 2008
Sorozat:Acta scientiarum mathematicarum 74 No. 3-4
Kulcsszavak:Matematika
Tárgyszavak:
Online Access:http://acta.bibl.u-szeged.hu/16268
Leíró adatok
Tartalmi kivonat:In this note we construct an operator T on a (separable, complex) Hilbert space such that for every nonzero vector x, the sequence {||Tnx||}ngN is dense in R+, but despite this, T is not hypercyclic (i.e., no vector in H has a dense orbit). In addition, this operator has the property that there are subsequences {r n } and {qn} of N such that Trn —> 0 and TQn —> +oo (properly defined) in the strong operator topology. Finally, neither T nor T* has point spectrum. This partially answers a question in [5] and provides a counterexample to some reasonable conjectures.
Terjedelem/Fizikai jellemzők:743-756
ISSN:0001-6969