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20142024
most citedNormal amenable subgroups of the automorphism group of the full shift

26 citations · 94 across the 17 of their papers we have counts for

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8 papers · 1 filter

math.GR2023

Poisson Boundary for Upper-Triangular Groups

Anna Erschler, Josh Frisch, Mark Rychnovsky

We prove that finite entropy random walks on the torsion-free Baumslag group in dimension have non-trivial Poisson boundary. This is in contrast with the torsion case where t…

math.GR2022★ 3 cited

The Poisson boundary of hyperbolic groups without moment conditions

Kunal Chawla, Behrang Forghani, Joshua Frisch +1

We prove that the Poisson boundary of a random walk with finite entropy on a non-elementary hyperbolic group can be identified with its hyperbolic boundary, without assuming any mo…

math.GR2022

Poisson boundary of group extensions

Anna Erschler, Joshua Frisch

Given a finitely generated group, the well-known Stability Problem asks whether the non-triviality of the Poisson-Furstenberg boundary (which is equivalent to the existence of non-…

math.GR2019

Quotients by countable subgroups are hyperfinite

Joshua Frisch, Forte Shinko

We show that for any Polish group and any countable normal subgroup , the coset equivalence relation is a hyperfinite Borel equivalence relation. In par…

math.GR2018★ 2 cited

Non-virtually nilpotent groups have infinite conjugacy class quotients

Joshua Frisch, Pooya Vahidi Ferdowsi

We offer in this note a self-contained proof of the fact that a finitely generated group is not virtually nilpotent if and only if it has a quotient with the infinite conjugacy cla…

math.GR2018★ 21 cited

Choquet-Deny groups and the infinite conjugacy class property

Joshua Frisch, Yair Hartman, Omer Tamuz +1

A countable discrete group is called Choquet-Deny if for every non-degenerate probability measure on it holds that all bounded -harmonic functions are constant. We s…

math.GR2018★ 10 cited

Strong amenability and the infinite conjugacy class property

Joshua Frisch, Omer Tamuz, Pooya Vahidi Ferdowsi

A group is said to be strongly amenable if each of its proximal topological actions has a fixed point. We show that a finitely generated group is strongly amenable if and only if i…

math.GR2014★ 6 cited

Transitive graphs uniquely determined by their local structure

Joshua Frisch, Omer Tamuz

We show that the "grandfather graph" has the following property: it is the unique completion to a transitive graph of a large enough finite subgraph of itself.