activity
20152026
most citedOn Følner sets in topological groups

18 citations · 91 across the 28 of their papers we have counts for

collaborators

28 papers

math.FA2026

Whirliness beyond amenability

Yannik Höll, Friedrich Martin Schneider

Given a non-atomic standard probability space , we exhibit examples of non-amenable closed topological subgroups of whose natural near-action on …

math.GR2024

Amenability and skew-amenability of actions of topological groups

Vadim Alekseev, Hiroshi Ando, Friedrich Martin Schneider +1

We define and study notions of amenability and skew-amenability of continuous actions of topological groups on compact topological spaces. Our main motivation is the question under…

math.GR2023

On invariant means and pre-syndetic subgroups

Vladimir G. Pestov, Friedrich Martin Schneider

Beyond the locally compact case, equivalent notions of amenability diverge, and some properties no longer hold, for instance amenability is not inherited by topological subgroups.…

math.GR2022

Amenable equivalence relations, Kesten's property, and measurable lamplighters

Maksym Chaudkhari, Kate Juschenko, Friedrich Martin Schneider

We prove a characterization of the amenability of countable Borel equivalence relations in terms of the uniform Liouville property for group actions on their classes. Furthermore,…

math.OA2022★ 3 cited

Group von Neumann algebras, inner amenability, and unit groups of continuous rings

Friedrich Martin Schneider

We prove that, if a discrete group is not inner amenable, then the unit group of the ring of operators affiliated with the group von Neumann algebra of is non-amenable with…

cs.LG2022★ 1 cited

Intrinsic Dimension for Large-Scale Geometric Learning

Maximilian Stubbemann, Tom Hanika, Friedrich Martin Schneider

The concept of dimension is essential to grasp the complexity of data. A naive approach to determine the dimension of a dataset is based on the number of attributes. More sophistic…

math.GN2022

An Application of Farkas' Lemma to Finite-Valued Constraint Satisfaction Problems over Infinite Domains

Friedrich Martin Schneider, Caterina Viola

We show a universal algebraic local characterisation of the expressive power of finite-valued languages with domains of arbitrary cardinality and containing arbitrary many cost fun…

math.FA2022★ 3 cited

Concentration of invariant means and dynamics of chain stabilizers in continuous geometries

Friedrich Martin Schneider

We prove a concentration inequality for invariant means on topological groups, namely for such adapted to a chain of amenable topological subgroups. The result is based on an appli…

math.DS2022

Entropy of group actions beyond uniform lattices

Till Hauser, Friedrich Martin Schneider

Entropy of measure preserving or continuous actions of amenable discrete groups allows for various equivalent approaches. Among them are the ones given by the techniques developed…

math.GR2020★ 2 cited

Skew-amenability of topological groups

Kate Juschenko, Friedrich Martin Schneider

We study skew-amenable topological groups, i.e., those admitting a left-invariant mean on the space of bounded real-valued functions left-uniformly continuous in the sense of Bourb…

math.PR2019★ 2 cited

Concentration of measure, classification of submeasures, and dynamics of

Friedrich Martin Schneider, Sławomir Solecki

Exhibiting a new type of measure concentration, we prove uniform concentration bounds for measurable Lipschitz functions on product spaces, where Lipschitz is taken with respect to…

math.FA2019★ 7 cited

The Liouville property and random walks on topological groups

Friedrich Martin Schneider, Andreas Thom

We study harmonic functions and Poisson boundaries for Borel probability measures on general (i.e., not necessarily locally compact) topological groups, and we prove that a second-…

cs.AI2018

Intrinsic dimension and its application to association rules

Tom Hanika, Friedrich Martin Schneider, Gerd Stumme

The curse of dimensionality in the realm of association rules is twofold. Firstly, we have the well known exponential increase in computational complexity with increasing item set…

math.MG2018

Equivariant dissipation in non-archimedean groups

Friedrich Martin Schneider

We prove that, if a topological group has an open subgroup of infinite index, then every net of tight Borel probability measures on UEB-converging to invariance dissipates…

cs.AI2018★ 5 cited

Intrinsic Dimension of Geometric Data Sets

Tom Hanika, Friedrich Martin Schneider, Gerd Stumme

The curse of dimensionality is a phenomenon frequently observed in machine learning (ML) and knowledge discovery (KD). There is a large body of literature investigating its origin…

math.FA2017★ 4 cited

Equivariant concentration in topological groups

Friedrich Martin Schneider

We prove that, if is a second-countable topological group with a compatible right-invariant metric and is a sequence of compactly supported Bor…

math.RA2017★ 7 cited

MacWilliams' extension theorem for infinite rings

Friedrich Martin Schneider, Jens Zumbrägel

Finite Frobenius rings have been characterized as precisely those finite rings satisfying the MacWilliams extension property, by work of Wood. In the present note we offer a genera…

math.GR2017★ 3 cited

About von Neumann's problem for locally compact groups

Friedrich Martin Schneider

We note a generalization of Whyte's geometric solution to the von Neumann problem for locally compact groups in terms of Borel and clopen piecewise translations. This strengthens a…

math.FA2017★ 10 cited

On amenability and groups of measurable maps

Vladimir G. Pestov, Friedrich Martin Schneider

We show that if is an amenable topological group, then the topological group of strongly measurable maps from into endowed with the topology of conve…

math.GR2016★ 18 cited

On Følner sets in topological groups

Friedrich Martin Schneider, Andreas Thom

We extend Følner's amenability criterion to the realm of general topological groups. Building on this, we show that a topological group is amenable if and only if its left tran…

math.LO2015★ 1 cited

A uniform Birkhoff theorem

Friedrich Martin Schneider

Garret Birkhoff's HSP theorem characterizes the classes of models of algebraic theories as those being closed with respect to homomorphic images, subalgebras, and products. In part…

math.RA2015★ 1 cited

Every simple compact semiring is finite

Friedrich Martin Schneider, Jens Zumbrägel

A Hausdorff topological semiring is called simple if every non-zero continuous homomorphism into another Hausdorff topological semiring is injective. Classical work by Anzai and Ka…

math.LO2015★ 5 cited

A topological characterisation of endomorphism monoids of countable structures

Manuel Bodirsky, Friedrich Martin Schneider

A topological monoid is isomorphic to an endomorphism monoid of a countable structure if and only if it is separable and has a compatible complete ultrametric such that composition…

math.DS2015★ 5 cited

Topological Entropy of Formal Languages

Friedrich Martin Schneider, Daniel Borchmann

We introduce the notion of topological entropy of a formal languages as the topological entropy of the minimal topological automaton accepting it. Using a characterization of this…