Abstract
We extend the concept of Arens regularity of a Banach algebra \(\mathcal{A}\) to the case that there is an \(\mathcal{O}\) -module structure on \(\mathcal{A}\) , and show that when S is an inverse semigroup with totally ordered subsemigroup E of idempotents, then A=ℓ 1(S) is module Arens regular if and only if an appropriate group homomorphic image of S is finite. When S is a discrete group, this is just Young’s theorem which asserts that ℓ 1(S) is Arens regular if and only if S is finite.
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Communicated by Jerome A. Goldstein.
An erratum to this article can be found at http://dx.doi.org/10.1007/s00233-009-9157-x
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Rezavand, R., Amini, M., Sattari, M.H. et al. Module Arens regularity for semigroup algebras. Semigroup Forum 77, 300–305 (2008). https://doi.org/10.1007/s00233-008-9075-3
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DOI: https://doi.org/10.1007/s00233-008-9075-3