Abstract
In this work, given a unital Banach algebra $\mathcal{A}$ and $a\in \mathcal{A}$ such that $a$ has a Moore--Penrose inverse $a^\dagger$, it will be characterized when $aa^\dagger- a^\dagger a$ is invertible. A particular subset of this class of objects will also be studied. In addition, perturbations of this class of elements will be studied. Finally, the Banach space operator case will be also considered.
Citation
Julio Benítez. Enrico Boasso. Vladimir Rakočević. "Co-EP Banach algebra elements." Banach J. Math. Anal. 9 (1) 27 - 41, 2015. https://doi.org/10.15352/bjma/09-1-3
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