5 papers · 1 filter
Topological full groups, invertible isometries, and automorphisms of groupoid algebras
Eusebio Gardella, Mathias Palmstrøm, Hannes Thiel
We show that the topological full group of a Hausdorff ample groupoid with compact unit space coincides with the group of homotopy classes of invertible isometries in pseudofunctio…
Exotic -completions of étale groupoids
Mathias Palmstrøm
We generalize the ideal completions of countable discrete groups, as introduced by Brown and Guentner, to second countable Hausdorff étale groupoids. Specifically, to every pair c…
Rigidity of pseudofunction algebras of ample groupoids
Eusebio Gardella, Mathias Palmstrøm, Hannes Thiel
We show that a Hausdorff, ample groupoid can be completely recovered from the -norm completion of . More generally, we show that this is also the…
K-theory invariance of -operator algebras associated with étale groupoids of strong subexponential growth
Are Austad, Eduard Ortega, Mathias Palmstrøm
We introduce the notion of (strong) subexponential growth for étale groupoids and study its basic properties. In particular, we show that the K-groups of the associated groupoid $…
Exotic groupoid -algebras associated to double groupoids
Mathias Palmstrøm
We consider a class of partial action groupoids called double groupoids which are constructed from pairs of subgroups satisfying similar conditions to those of a matched pair of gr…