Ultrapowers of $\ell^1$-Munn algebras and its application to semigroup algebras

Authors

  • Maedeh Soroushmehr University of Isfahan

Keywords:

Banach algebra. ultrapower, amenability. $\ell^1$-Munn algebra.

Abstract

In this work, we study and investigate the ultrapowers of $\ell^1$-Munn algebras. Then we show that the class of $\ell^1$-Munn algebras are stable under ultrapowers. Finally, applying this result to semigroup algebras, we show that for a semigroup $S$, ultra-amenability of $\ell^1(S)$ and amenability of the second dual $\ell^1(S)''$ are equivalent. 10.1017/S0004972711003339

Published

2012-10-22

Issue

Vol. 86 No. 3 (2012)

Section

Articles
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