On twisted higher-rank graph 𝐶*-algebras

Autor: David Pask, Aidan Sims, Alex Kumjian
Rok vydání: 2015
Předmět:
Zdroj: Transactions of the American Mathematical Society. 367:5177-5216
ISSN: 1088-6850
0002-9947
DOI: 10.1090/s0002-9947-2015-06209-6
Popis: We define the categorical cohomology of a k k -graph Λ \Lambda and show that the first three terms in this cohomology are isomorphic to the corresponding terms in the cohomology defined in our previous paper. This leads to an alternative characterisation of the twisted k k -graph C ∗ C^* -algebras introduced there. We prove a gauge-invariant uniqueness theorem and use it to show that every twisted k k -graph C ∗ C^* -algebra is isomorphic to a twisted groupoid C ∗ C^* -algebra. We deduce criteria for simplicity, prove a Cuntz-Krieger uniqueness theorem and establish that all twisted k k -graph C ∗ C^* -algebras are nuclear and belong to the bootstrap class.
Databáze: OpenAIRE