Annali di Matematica Pura ed Applicata

, Volume 83, Issue 1, pp 185–194 | Cite as

Commutators of two operators one of which is unbounded and semi-normal

  • Mendel David


The concept of semi-normality and hyponormality are defined for unbounded operators in Hilbert Space and Commutators AB-BA, with A unbounded and seminormal and with B bounded, are studied. Four theorems are proved. Two of them are generalizations of results of C. R. Putman.


Hilbert Space Unbounded Operator 
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    F. Riesz andB. Sz. Nagy,Functional Analysis, Frederick Ungar Pnb. Co. N.Y. (1955).Google Scholar

Copyright information

© Nicola Zanichelli Editore 1969

Authors and Affiliations

  • Mendel David

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