Module contractibility for semigroup algebras

Document Type: Research Articles


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


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

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