Results 1 to 10 of about 67 (67)
Żuk’s criterion for Banach spaces and random groups
Forum of Mathematics, Sigma, 2023 We prove a Banach version of Żuk’s criterion for groups acting on partite (i.e., colorable) simplicial complexes. Using this new criterion, we derive a new fixed point theorem for random groups in the Gromov density model with respect to several classes ...
Izhar Oppenheim
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Tits Alternative for $2$ -dimensional $\mathrm {CAT}(0)$ complexes
Forum of Mathematics, Pi, 2022 We prove the Tits Alternative for groups acting on $2$ -dimensional $\mathrm {CAT}(0)$ complexes with a bound on the order of the cell stabilisers.
Damian Osajda, Piotr Przytycki
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Cusps, Kleinian groups, and Eisenstein series
Forum of Mathematics, Sigma, 2023 We study the Eisenstein series associated to the full rank cusps in a complete hyperbolic manifold. We show that given a Kleinian group $\Gamma
Beibei Liu, Shi Wang
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On subset sum problem in branch groups [PDF]
Groups, Complexity, Cryptology, 2020 We consider a group-theoretic analogue of the classic subset sum problem. In this brief note, we show that the subset sum problem is NP-complete in the first Grigorchuk group.
Andrey Nikolaev, Alexander Ushakov
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Curve graphs for Artin–Tits groups of type B, A∼ and C∼ are hyperbolic
Transactions of the London Mathematical Society, 2021 The graph of irreducible parabolic subgroups is a combinatorial object associated to an Artin–Tits group A defined so as to coincide with the curve graph of the (n+1)‐times punctured disk when A is Artin's braid group on (n+1) strands.
Matthieu Calvez +1 more
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The Asymptotic Statistics of Random Covering Surfaces
Forum of Mathematics, Pi, 2023 Let $\Gamma _{g}$ be the fundamental group of a closed connected orientable surface of genus $g\geq 2$ . We develop a new method for integrating over the representation space $\mathbb {X}_{g,n}=\mathrm {Hom}(\Gamma _{g},S_{n})$ , where
Michael Magee, Doron Puder
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Growth functions for some uniformly amenable groups
Open Mathematics, 2017 We present a simple constructive proof of the fact that every abelian discrete group is uniformly amenable. We improve the growth function obtained earlier and find the optimal growth function in a particular case.
Dronka Janusz +3 more
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EQUIVARIANT GEOMETRY OF BANACH SPACES AND TOPOLOGICAL GROUPS
Forum of Mathematics, Sigma, 2017 We study uniform and coarse embeddings between Banach spaces and topological groups. A particular focus is put on equivariant embeddings, that is, continuous cocycles associated to continuous affine isometric actions of topological groups on separable ...
CHRISTIAN ROSENDAL
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Random groups and nonarchimedean lattices
Forum of Mathematics, Sigma, 2014 We consider models of random groups in which the typical group is of intermediate rank (in particular, it is not hyperbolic). These models are parallel to Gromov’s well-known constructions, and include for example a ‘density model’ for groups of ...
SYLVAIN BARRÉ, MIKAËL PICHOT
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CANNON–THURSTON MAPS FOR KLEINIAN GROUPS
Forum of Mathematics, Pi, 2017 We show that Cannon–Thurston maps exist for degenerate free groups without parabolics, that is, for handlebody groups. Combining these techniques with earlier work proving the existence of Cannon–Thurston maps for surface groups, we show that Cannon ...
MAHAN MJ
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