中文

Divisibility and Real Rank Zero

算子代数 2026-05-22 v1

摘要

Let AA be a simple separable exact CC^*-algebra that has traces. We show the following existed regularity properties are equivalent: \quad(1) l(A)/JAl^\infty(A)/J_A has real rank zero, where JAJ_A is the trace kernel ideal. \quad(2) AA is tracially almost divisible. \quad(3) AA is tracially mm-almost divisible for some mN{0}.m\in\N\cup\{0\}. \quad(4) AA has tracial approximate oscillation zero. \quad(5) AA has Property (TM). We also show that for an algebraically simple separable stable rank one \CA\ BB with non-empty compact T(B){\rm T}(B) and locally finite nuclear dimension, its uniform tracial completion (\olB\rT(B),\rT(B))(\ol B^{\rT(B)}, \rT(B)) is hyperfinite, type II1,{\rm II_1}, and isomorphic to (R\rT(B),\rT(B))({\cal R}_{\rT(B)},\rT(B)). Furthermore, \olBT(B)\ol{B}^{{\rm T}(B)} is pure, has real rank zero and stable rank one, and satisfies \rT(\olB\rT(B))=\rT(B).\rT (\ol B^{\rT(B)} )= \rT(B). Consequently, every simple separable unital diagonal AH-algebra VV (e.g. Villadsen algebras of the first type) has the following tracial strict comparison: For every a,bV+,a,b\in V_+, if dτ(a)<dτ(b)d_\tau(a)<d_\tau(b) holds for all traces τ\rT(V),\tau\in\rT(V), then there is a sequence {rn}V\{r_n\}\subset V such that limnarnbrn2,\rT(V)=0.\lim_n\|a-r_n^*br_n\|_{2,\rT(V)}=0.

关键词

引用

@article{arxiv.2605.21655,
  title  = {Divisibility and Real Rank Zero},
  author = {Xuanlong Fu},
  journal= {arXiv preprint arXiv:2605.21655},
  year   = {2026}
}

备注

30 pages