Let A be a complex unital Banach algebra. We characterize elements belonging to Γ(A), the set of elements central modulo the radical. Our result extends and unifies several known characterizations of elements in Γ(A).
@article{bwmeta1.element.bwnjournal-article-smv120i1p47bwm,
author = {Matej Bre\v sar and Peter \v Semrl},
title = {Spectral characterizations of central elements in Banach algebras},
journal = {Studia Mathematica},
volume = {119},
year = {1996},
pages = {47-52},
zbl = {0868.46036},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv120i1p47bwm}
}
Brešar, Matej; Šemrl, Peter. Spectral characterizations of central elements in Banach algebras. Studia Mathematica, Tome 119 (1996) pp. 47-52. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv120i1p47bwm/
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