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Edwards' condition for quasitraces on C*-algebras

Published online by Cambridge University Press:  08 April 2020

Ramon Antoine
Departament de Matemàtiques, Universitat Autònoma de Barcelona, 08193Bellaterra, Barcelona, Spain (;
Francesc Perera
Departament de Matemàtiques, Universitat Autònoma de Barcelona, 08193Bellaterra, Barcelona, Spain (;
Leonel Robert
Department of Mathematics, University of Louisiana at Lafayette, Lafayette, LA70504-1010, USA (
Hannes Thiel
Mathematisches Institut, Universität Münster, Einsteinstr. 62, 48149 Münster, Germany (
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We prove that Cuntz semigroups of C*-algebras satisfy Edwards' condition with respect to every quasitrace. This condition is a key ingredient in the study of the realization problem of functions on the cone of quasitraces as ranks of positive elements. In the course of our investigation, we identify additional structure of the Cuntz semigroup of an arbitrary C*-algebra and of the cone of quasitraces.

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