On nuclearity of the C∗-algebra of an inverse semigroup

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Massoud Amini
Mahmood Khoshkam

We show that the universal groupoid of an inverse semigroup S is topologically (measurewise) amenable if and only if S is hyperfinite and all members of a family of subsemigroups of S indexed by the spectrum of the commutative C∗-algebra C∗(ES) on the idempotents ES of S are amenable. Thereby we solve some problems raised by A. L. T. Paterson.

Paraules clau
inverse semigroup, universal groupoid, amenability, nuclearity

Article Details

Com citar
Amini, Massoud; Khoshkam, Mahmood. «On nuclearity of the C∗-algebra of an inverse semigroup». Publicacions Matemàtiques, 2020, vol.VOL 64, núm. 2, p. 499–511, http://raco.cat/index.php/PublicacionsMatematiques/article/view/371195.
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