TY - JOUR T1 - Contractibility and idempotents in Banach algebras TT - جبرهای باناخ انقباض پذیر JF - jsci JO - jsci VL - 18 IS - 48 UR - http://jsci.khu.ac.ir/article-1-1187-en.html Y1 - 2007 SP - 146 EP - 154 KW - Contractible Banach algebras KW - Minimal idempotent N2 - Let be a Banach algebra. It is shown that a contractible ideal of a Banach algebra is complemented by its annihilator. Then, it is proved the existence of minimal central idempotents in a contractible Banach algebra with a nonzero character. Moreover, the notion of b-contractibility and one of its equivalent forms are introduced. Throgh an example, it is shown that b-contractibility is strictly weaker than contractibility. M3 ER -