On character amenability of semigroup algebras

  • R. Gholami
  • H. RahimiEmail author


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.


Character amenability Character amenability modulo an ideal Semigroup algebra 

Mathematics Subject Classification

43A07 46H25 



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

Compliance with ethical standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


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Copyright information

© Unione Matematica Italiana 2019

Authors and Affiliations

  1. 1.Department of Mathematics, Faculty of Science, Central Tehran BranchIslamic Azad UniversityTehranIran

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