On character amenability of semigroup algebras


The main purpose of this paper is to investigate the character amenability of semigroup algebras. In this regard, the new concept character amenability modulo an ideal of Banach algebras are introduced. For a large class of semigroups such as E-inversive E-semigroup and eventually inverse semigroups, it is shown that the semigroup S is amenable if and only if the semigroup algebra \(l^1(S)\) is character amenable modulo an ideal. Some characterizations of character amenability modulo an ideal of Banach algebras are studied and interesting examples are presented.

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The authors wish to thank the referees and the editor for their useful comments and suggestions.

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Correspondence to H. Rahimi.

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Gholami, R., Rahimi, H. On character amenability of semigroup algebras. Boll Unione Mat Ital 12, 517–524 (2019). https://doi.org/10.1007/s40574-018-00189-y

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  • Character amenability
  • Character amenability modulo an ideal
  • Semigroup algebra

Mathematics Subject Classification

  • 43A07
  • 46H25