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Essential character amenability of semigroup algebras

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Abstract

Let S be a foundation topological semigroup and \(M_a(S)\) the space of all measures \(\mu \in M(S)\) for which the maps \(x\longmapsto |\mu |*\delta _{x}\) and \(x\longmapsto \delta _{x}*|\mu |\) from S into M(S) are weakly continuous. In the present paper, we introduce and study the concept of \(\phi\)-amenability for S and investigate the relations between \(\phi\)-amenability of S and essential \(\widehat{\phi }\)-amenability of \(M_a(S)\), where \(\phi\) is a character on S and \(\widehat{\phi }\) is the extension of \(\phi\) to \(M_a(S)\).

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Correspondence to Hamid Sadeghi Nahrekhalaji.

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Communicated by Anthony To-Ming Lau.

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Nahrekhalaji, H.S. Essential character amenability of semigroup algebras. Semigroup Forum 102, 528–542 (2021). https://doi.org/10.1007/s00233-020-10155-w

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