Dynamic asymptotic dimension and Matui's HK conjecture

C Bönicke, C Dell'Aiera, J Gabe… - Proceedings of the …, 2023 - Wiley Online Library
We prove that the homology groups of a principal ample groupoid vanish in dimensions
greater than the dynamic asymptotic dimension of the groupoid (as a side‐effect of our …

Purely Infinite Locally Compact Hausdorff étale Groupoids and Their C*-algebras

X Ma - International Mathematics Research Notices, 2022 - academic.oup.com
In this paper, we introduce properties including groupoid comparison, pure infiniteness, and
paradoxical comparison as well as a new algebraic tool called groupoid semigroup for …

[PDF][PDF] On tracial Z-stability of simple non-unital C*-algebras

J Castillejos, K Li, G Szabo - Canadian Journal Of Mathematics …, 2023 - lirias.kuleuven.be
ON TRACIAL Z-STABILITY OF SIMPLE NON-UNITAL C∗-ALGEBRAS Introduction The Jiang-Su
algebra Z has become a cornerstone in the cl Page 1 ON TRACIAL Z-STABILITY OF SIMPLE …

Diagonal comparison of ample C*-diagonals

G Kopsacheilis, W Winter - arXiv preprint arXiv:2410.05967, 2024 - arxiv.org
We introduce diagonal comparison, a regularity property of diagonal pairs where the sub-C*-
algebra has totally disconnected spectrum, and establish its equivalence with the …

Strict comparison for -algebras arising from almost finite groupoids

P Ara, C Bönicke, J Bosa, K Li - Banach Journal of Mathematical Analysis, 2020 - Springer
In this paper we show that for an almost finite minimal ample groupoid G, its reduced C^* C∗-
algebra C_r^*(G) C r∗(G) has real rank zero and strict comparison even though C_r^*(G) C …

Fiberwise amenability of ample\'{e} tale groupoids

X Ma - arXiv preprint arXiv:2110.11548, 2021 - arxiv.org
Let $\mathcal {G} $ be a locally compact $\sigma $-compact Hausdorff ample groupoid on a
compact space. In this paper, we further examine the (ubiquitous) fiberwise amenability …

A comprehensive characterization of Property A and almost finiteness

G Elek, Á Timár - arXiv preprint arXiv:2308.14554, 2023 - arxiv.org
Three important properties of groups, amenability, Property A and almost finiteness, are in
our focus, in the wider context of general countable bounded degree graphs. A graph is …

Tracial states on groupoid -algebras and essential freeness

K Li, J Zhang - arXiv preprint arXiv:2401.15546, 2024 - arxiv.org
Let $\mathcal {G} $ be a locally compact Hausdorff\'{e} tale groupoid. We call a tracial state
$\tau $ on a general groupoid $ C^* $-algebra $ C_\nu^*(\mathcal {G}) $ canonical if …

The diagonal dimension of sub-C*-algebras

K Li, HC Liao, W Winter - arXiv preprint arXiv:2303.16762, 2023 - arxiv.org
We introduce diagonal dimension, a version of nuclear dimension for diagonal sub-C*-
algebras (sometimes also referred to as diagonal C*-pairs). Our concept has good …

Topological full groups

O Tanner - 2024 - theses.gla.ac.uk
We develop our understanding of topological full groups, a way of constructing examples of
infinite simple groups with finiteness properties from ample groupoids. Our results are …