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Topologically left invariant means on semigroup algebras

Ali Ghaffari
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Abstract

Let $M(S)$ be the Banach algebra of all bounded regular Borel measures on a locally compact Hausdorff semitopological semigroup $S$ with variation norm and convolution as multiplication. We obtain necessary and sufficient conditions for $M(S)^{*}$ to have a topologically left invariant mean.

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Ali Ghaffari. 2005-12-14. Topologically left invariant means on semigroup algebras. https://arxiv.org/abs/math/0512319

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