Spectra of the difference, sum and product of idempotents

Mohamed Barraa, and Mohamed Boumazgour. "Spectra of the difference, sum and product of idempotents." Studia Mathematica 148.1 (2001): 1-3. <http://eudml.org/doc/285134>.

@article{MohamedBarraa2001,
abstract = {We give a simple proof of the relation between the spectra of the difference and product of any two idempotents in a Banach algebra. We also give the relation between the spectra of their sum and product.},
author = {Mohamed Barraa, Mohamed Boumazgour},
journal = {Studia Mathematica},
keywords = {pair of idempotents; quadratic element; Banach algebra},
language = {eng},
number = {1},
pages = {1-3},
title = {Spectra of the difference, sum and product of idempotents},
url = {http://eudml.org/doc/285134},
volume = {148},
year = {2001},
}

TY - JOUR
AU - Mohamed Barraa
AU - Mohamed Boumazgour
TI - Spectra of the difference, sum and product of idempotents
JO - Studia Mathematica
PY - 2001
VL - 148
IS - 1
SP - 1
EP - 3
AB - We give a simple proof of the relation between the spectra of the difference and product of any two idempotents in a Banach algebra. We also give the relation between the spectra of their sum and product.
LA - eng
KW - pair of idempotents; quadratic element; Banach algebra
UR - http://eudml.org/doc/285134
ER -