Geodesic
Sums of Idempotents in Banach Algebras
Canadian mathematical bulletin, Tome 31 (1988) no. 4, pp. 448-451

Voir la notice de l'article provenant de la source Cambridge University Press

We prove that the sum of two idempotents is in a Banach algebra is itself an idempotent if and only if it is power-bounded.
DOI : 10.4153/CMB-1988-065-4
Mots-clés : 46H05 
Kalton, N. J. Sums of Idempotents in Banach Algebras. Canadian mathematical bulletin, Tome 31 (1988) no. 4, pp. 448-451. doi: 10.4153/CMB-1988-065-4
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