ArticleOriginal scientific text
Title
Derivations into iterated duals of Banach algebras
Authors 1, 2, 3
Affiliations
- Department of Pure Mathematics, University of of Leeds, Leeds LS2 9JT, England
- Department of Mathematics, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Mathematics, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
Abstract
We introduce two new notions of amenability for a Banach algebra A. The algebra A is n-weakly amenable (for n ∈ ℕ) if the first continuous cohomology group of A with coefficients in the n th dual space is zero; i.e., . Further, A is permanently weakly amenable if A is n-weakly amenable for each n ∈ ℕ.
We begin by examining the relations between m-weak amenability and n-weak amenability for distinct m,n ∈ ℕ. We then examine when Banach algebras in various classes are n-weakly amenable; we study group algebras, C*-algebras, Banach function algebras, and algebras of operators. Our results are summarized and some open questions are raised in the final section.
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