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arXiv · 2003.03858

K-theory for semigroup C*-algebras and partial crossed products

Xin Li
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Abstract

Using the Baum-Connes conjecture with coefficients, we develop a K-theory formula for reduced C*-algebras of strongly $0$-$E$-unitary inverse semigroups, or equivalently, for certain reduced partial crossed products. In the case of semigroup C*-algebras, we obtain a generalization of previous K-theory results of Cuntz, Echterhoff and the author without having to assume the Toeplitz condition. As applications, we discuss semigroup C*-algebras of Artin monoids, Baumslag-Solitar monoids, one-relator monoids, C*-algebras generated by right regular representations of semigroups from number theory, and C*-algebras of inverse semigroups arising in the context of tilings.

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BibTeXRIS

Xin Li. 2020-03-08. K-theory for semigroup C*-algebras and partial crossed products. https://doi.org/10.1007/s00220-021-04194-9

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