Products of EP operators on Hilbert spaces
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- by Dragan S. Djordjević PDF
- Proc. Amer. Math. Soc. 129 (2001), 1727-1731 Request permission
Abstract:
A Hilbert space operator $A$ is called the EP operator if the range of $A$ is equal to the range of its adjoint $A^{*}$. In this article necessary and sufficient conditions are given for a product of two EP operators with closed ranges to be an EP operator with a closed range. Thus, a generalization of the well-known result of Hartwig and Katz (Linear Algebra Appl. 252 (1997), 339–345) is given.References
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- Robert E. Hartwig and Irving J. Katz, On products of EP matrices, Linear Algebra Appl. 252 (1997), 339–345. MR 1428641, DOI 10.1016/0024-3795(95)00693-1
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Additional Information
- Dragan S. Djordjević
- Affiliation: Department of Mathematics, Faculty of Philosophy, University of Niš, Ćirila i Metodija 2, 18000 Niš, Yugoslavia
- Email: dragan@archimed.filfak.ni.ac.yu, dragan@filfak.filfak.ni.ac.yu
- Received by editor(s): May 4, 1999
- Received by editor(s) in revised form: September 17, 1999
- Published electronically: October 31, 2000
- Communicated by: Joseph A. Ball
- © Copyright 2000 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 129 (2001), 1727-1731
- MSC (2000): Primary 47A05, 15A09
- DOI: https://doi.org/10.1090/S0002-9939-00-05701-4
- MathSciNet review: 1814103