Products of EP operators on Hilbert spaces

Djordjević, Dragan

doi:10.1090/S0002-9939-00-05701-4

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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