Periodica Mathematica Hungarica

, Volume 63, Issue 2, pp 191–203 | Cite as

On the commutant of asymptotically non-vanishing contractions

  • György Pál GehérEmail author
  • László Kérchy


The injectivity of the commutant mapping of asymptotically nonvanishing contractions is examined. We show that this mapping can be injective even in the presence of a non-trivial stable subspace. Various characterizations of injectivity are provided.

Key words and phrases

commutant mapping unitary asymptote contraction 

Mathematics subject classification numbers

47A45 47A15 47B47 


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2011

Authors and Affiliations

  1. 1.Bolyai InstituteUniversity of SzegedSzegedHungary

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