文摘
We study the relation between the module and Hochschild cohomology groups of Banach algebras.We show that, for every commutative Banach A-A-bimodule X and every k ?N, the seminormed spaces H A k (A,X*) and H k (A /J,X*) are isomorphic, where J is a specific closed ideal of A. As an example, we show that, for an inverse semigroup S with the set of idempotents E, where ?sup>1(E) acts on ?sup>1(S) by multiplication on the right and trivially on the left, the first module cohomology \(H_{{\ell ^1}\left( E \right)}^1\) (?sup>1(S), ?sup>1(G S )(2n+1)) is trivial for each n ?N, where G S is the maximal group homomorphic image of S. Also, the second module cohomology \(H_{{\ell ^1}\left( E \right)}^2\) (?sup>1(S), ?sup>1(G S )(2n+1)) is a Banach space. Keywords module cohomology group Hochschild cohomology group inverse semigroup semigroup algebra