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arXiv · 1112.3576

The descriptive set theory of C$^*$-algebra invariants

Ilijas Farah·Andrew S. Toms·Asger Törnquist
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Abstract

We establish the Borel computability of various C$^*$-algebra invariants, including the Elliott invariant and the Cuntz semigroup. As applications we deduce that AF algebras are classifiable by countable structures, and that a conjecture of Winter and the second author for nuclear separable simple C*-algebras cannot be disproved by appealing to known standard Borel structures on these algebras.

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Ilijas Farah, Andrew S. Toms, Asger Törnquist. 2012-04-21. The descriptive set theory of C$^*$-algebra invariants. https://arxiv.org/abs/1112.3576

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