2 papers
math.LO2025
Hyper-u-amenablity and Hyperfiniteness of Treeable Equivalence Relations
Petr Naryshkin, Andrea Vaccaro
We introduce the notions of u-amenability and hyper-u-amenability for countable Borel equivalence relations, strong forms of amenability that are implied by hyperfiniteness. We sho…
math.OA2024
Actions on classifiable C*-algebras without equivariant property (SI)
Eusebio Gardella, Julian Kranz, Andrea Vaccaro
We exhibit examples of actions of countable discrete groups on both simple and non-simple nuclear stably finite C*-algebras that are tracially amenable but not amenable. We further…