3 papers
math.OA2026
A dichotomy for inverse-semigroup crossed products via dynamical Cuntz semigroups
Becky Armstrong, Lisa Orloff Clark, Astrid an Huef +2
We characterise stable finiteness and pure infiniteness of the essential crossed product of a C*-algebra by an action of an inverse semigroup. Under additional assumptions, we prov…
math.OA2026
Algebraic singular functions are not always dense in the ideal of -singular functions
Diego MartÃnez, Nóra Szakács
We give the first examples of étale (non-Hausdorff) groupoids whose -algebras contain singular elements that cannot be approximated by singular elements in $\mat…
math.OA2025
Essential groupoid amenability and nuclearity of groupoid C*-algebras
Alcides Buss, Diego MartÃnez
We give an alternative construction of the essential -algebra of an étale groupoid, along with an ``amenability'' notion for such groupoids that is implied by the nuclearity…