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Counterexamples Related to Commutators of Unbounded Operators

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Abstract

The present paper is exclusively devoted to examples and counterexamples about commutators and self commutators of unbounded operators on a Hilbert space. As a bonus, we provide a simpler counterexample than McIntosh’s famous example obtained some while ago.

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Acknowledgements

The author wishes to thank the referee for all his/her remarks and suggestions which have been necessary to improve some parts of the paper.

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  1. Department of Mathematics, University of Oran 1, Ahmed Ben Bella, B.P. 1524, El Menouar Oran, 31000, Algeria

    Mohammed Hichem Mortad

  2. Oran, Algeria

    Mohammed Hichem Mortad

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  1. Mohammed Hichem Mortad
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Correspondence to Mohammed Hichem Mortad.

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Mortad, M.H. Counterexamples Related to Commutators of Unbounded Operators. Results Math 74, 174 (2019). https://doi.org/10.1007/s00025-019-1100-1

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