# Unbounded quasitraces, stable finiteness and pure infiniteness

@article{Pask2017UnboundedQS, title={Unbounded quasitraces, stable finiteness and pure infiniteness}, author={David Pask and Adam Sierakowski and Aidan Sims}, journal={arXiv: Operator Algebras}, year={2017} }

We prove that if A is a \sigma-unital exact C*-algebra of real rank zero, then every state on K_0(A) is induced by a 2-quasitrace on A. This yields a generalisation of Rainone's work on pure infiniteness and stable finiteness of crossed products to the non-unital case. It also applies to k-graph algebras associated to row-finite k-graphs with no sources. We show that for any k-graph whose C*-algebra is unital and simple, either every twisted C*-algebra associated to that k-graph is stably…

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