3 papers
math.GR2023
Small cancellation groups with and without sigma-compact Morse boundary
Stefanie Zbinden
We provide examples of classical small-cancellation groups which have non-sigma-compact Morse boundary. These are first known examples of groups with non-sigma-compact Morse bounda…
math.GR2023
Characterising quasi-isometries of the free group
Antoine Goldsborough, Stefanie Zbinden
We introduce the notion of mixed subtree quasi-isometries, which are self quasi-isometries of regular trees built in a specific inductive way. We then show that any self quasi-isom…
math.GR2023
Some properties of Markov chains on the free group
Antoine Goldsborough, Stefanie Zbinden
Random walks cannot, in general, be pushed forward by quasi-isometries. Tame Markov chains were introduced as a `quasi-isometry invariant' are a generalization of random walks. In…