English

Higher homotopy groups of Cuntz classes

Operator Algebras 2022-10-27 v1

Abstract

Let AA be a unital simple separable exact C^*-algebra which is approximately divisible and of real rank zero. We prove that the set of positive elements in AA with a fixed non-compact Cuntz class has vanishing homotopy groups. Combined with work of S. Zhang for the case of compact elements, this gives a complete calculation of the homotopy groups of Cuntz classes for these algebras. Examples covered include approximately finite-dimensional (AF) algebras and irrational noncommutative tori.

Keywords

Cite

@article{arxiv.2210.14371,
  title  = {Higher homotopy groups of Cuntz classes},
  author = {Andrew S. Toms},
  journal= {arXiv preprint arXiv:2210.14371},
  year   = {2022}
}

Comments

10 pages, no figures

R2 v1 2026-06-28T04:30:48.054Z