Elements of C*-algebras commuting with their Moore-Penrose inverse
Volume 139 / 2000
Studia Mathematica 139 (2000), 81-90
DOI: 10.4064/sm-139-1-81-90
Abstract
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.
