Approximate biprojectivity and biflatness of some algebras over certain semigroups

Document Type : Research Article

Authors

1 Department of Mathematics‎, University of ‎Tabriz‎, ‎Tabriz‎, ‎Iran.

2 Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran.

Abstract

‎We investigate (bounded) approximate biprojectivity of $l^1(S)$ for uniformly locally finite inverse semigroups‎. ‎As a consequence‎, ‎we show that when $S=\mathcal{M}(G‎, ‎I)$ is the Brandt inverse semigroup‎, ‎then $l^1(S)$ is (boundedly) approximately biprojective if and only if $G$ is amenable‎. ‎Moreover‎, ‎we study biflatness and (bounded) approximate biprojectivity of the measure algebra $M(S)$ of a topological Brandt semigroup‎.

Keywords

References

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Journal of the Iranian Mathematical Society
Volume 1, Issue 2
December 2020
Pages 145-155

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