We give new necessary and sufficient conditions for an element of a C*-algebra to commute with its Moore-Penrose inverse. We then study conditions which ensure that this property is preserved under multiplication. As a special case of our results we recover a recent theorem of Hartwig and Katz on EP matrices.
@article{bwmeta1.element.bwnjournal-article-smv139i1p81bwm,
author = {J. Koliha},
title = {Elements of C*-algebras commuting with their Moore-Penrose inverse},
journal = {Studia Mathematica},
volume = {141},
year = {2000},
pages = {81-90},
zbl = {0963.46037},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv139i1p81bwm}
}
Koliha, J. Elements of C*-algebras commuting with their Moore-Penrose inverse. Studia Mathematica, Tome 141 (2000) pp. 81-90. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv139i1p81bwm/
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