Module contractibility for semigroup algebras

Subject Areas : Applied Mathematics

Abasalt Bodaghi ¹

1 - Department of Mathematics, Islamic Azad University, Garmsar Branch, Garmsar, Iran.

Received: 2015-09-28 Accepted : 2015-09-28 Published : 2013-12-01

Keywords: Banach module, module contractibleity, module derivation, inverse semi-groups,

Abstract :

In this paper, we nd the relationships between module contractibility of aBanach algebra and its ideals. We also prove that module contractibility ofa Banach algebra is equivalent to module contractibility of its module uniti-zation. Finally, we show that when a maximal group homomorphic image ofan inverse semigroup S with the set of idempotents E is nite, the moduleprojective tensor product l1(S)×l1(E)l1(S) is l1(E)-module contractible.

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