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Related papers: Non-abelian group structure on the Urysohn space

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Let $RG$ be the gruop ring of the group $G$ over ring $R$ and $\mathscr{U}(RG)$ be its unit group. Finding the structure of the unit group of a finite group ring is an old topic in ring theory. In, G. Tang et al: Unit Groups of Group…

Rings and Algebras · Mathematics 2020-04-08 Ali Ashja'

We present a general framework for automatic continuity results for groups of isometries of metric spaces. In particular, we prove automatic continuity property for the group of isometries of the Urysohn space and the Urysohn sphere, i.e.…

Logic · Mathematics 2019-04-10 Marcin Sabok

We study Ramsey-theoretic properties of several natural classes of finite ultrametric spaces, describe the corresponding Urysohn spaces and compute a dynamical invariant attached to their isometry groups.

Combinatorics · Mathematics 2014-01-07 L. Nguyen Van Thé

We give a construction of the Gurarij space, analogous to Katetov's construction of the Urysohn space. The adaptation of Katetov's technique uses a generalisation of the Arens-Eells enveloping space to metric space with a distinguished…

Logic · Mathematics 2012-08-14 Itaï Ben Yaacov

In this survey article, we present some panorama of groups acting on metric spaces of non-positive curvature. We introduce the main examples and their rigidity properties , we show the links between algebraic or analytic properties of the…

Differential Geometry · Mathematics 2021-04-21 Bruno Duchesne

We construct Graev ultrametrics on free products of groups with two-sided invariant ultrametrics and HNN extensions of such groups. We also introduce a notion of a free product of general Polish groups and prove, in particular, that two…

Group Theory · Mathematics 2013-10-11 Konstantin Slutsky

An almost Abelian group is a non-Abelian Lie group with a codimension 1 Abelian subgroup. This paper investigates invariant Hermitian and K\"{a}hler structures on connected complex almost Abelian groups. We find explicit formulas for the…

Differential Geometry · Mathematics 2023-08-21 Zhirayr Avetisyan , Abigail Brauer , Oderico-Benjamin Buran , Jimmy Morentin , Tianyi Wang

We study some close relationships between the classes of transitive, fully transitive and Krylov transitive torsion-free Abelian groups. In addition, as an application of the achieved assertions, we resolve some oldstanding problems, posed…

Rings and Algebras · Mathematics 2021-10-12 Andrey R. Chekhlov , Peter V. Danchev , Patrick W. Keef

Using classical results of infinite-dimensional geometry, we show that the isometry group of the Urysohn space, endowed with its usual Polish group topology, is homeomorphic to the separable Hilbert space. The proof is basedon a lemma about…

Metric Geometry · Mathematics 2009-11-22 Julien Melleray

In this paper we study the existence of free non-abelian subgroups in non-central permutable subgroups of general skew linear groups and locally finite group algebras.

Rings and Algebras · Mathematics 2019-12-23 Le Qui Danh , Mai Hoang Bien , Bui Xuan Hai

We prove the equivalence of the two important facts about finite metric spaces and universal Urysohn metric spaces $\Bbb U$, namely theorem A and theorem B below: Theorem A (Approximation): The group of isometry $ISO(\Bbb U)$ contains…

Metric Geometry · Mathematics 2008-04-01 A. Vershik

Given a finitely generated group $\Gamma$, we study the space ${\rm Isom}(\Gamma,{\mathbb Q\mathbb U})$ of all actions of $\Gamma$ by isometries of the rational Urysohn metric space ${\mathbb Q\mathbb U}$, where ${\rm Isom}(\Gamma,{\mathbb…

Logic · Mathematics 2011-04-19 Christian Rosendal

We study isometric $G$-spaces and the question of when their maximal equivariant compactification is the Gromov compactification (meaning that it coincides with the compactification generated by the distance functions to points). Answering…

Dynamical Systems · Mathematics 2021-01-14 Tomás Ibarlucía , Michael Megrelishvili

We construct two abelian varieties over $\mathbb{Q}$ which are not isomorphic, but have isomorphic Mordell--Weil groups over every number field, isomorphic Tate modules and equal values for several other invariants.

Number Theory · Mathematics 2025-08-04 Jamie Bell

We study the metric and topological properties of the space $\mathscr{D}(G)$ of left-invariant hyperbolic pseudometrics on the non-elementary hyperbolic group $G$ that are quasi-isometric to a word metric, up to rough similarity. This space…

Group Theory · Mathematics 2022-09-21 Eduardo Oregón-Reyes

We use the Fradkin-Vasiliev procedure to construct the full set of non-abelian cubic vertices for totally symmetric higher spin gauge fields in anti-de Sitter space. The number of such vertices is given by a certain tensor-product…

High Energy Physics - Theory · Physics 2015-06-12 Nicolas Boulanger , Dmitry Ponomarev , E. D. Skvortsov

Theories of classification distinguish classes with some good structure theorem from those for which none is possible. Some classes (dense linear orders, for instance) are non-classifiable in general, but are classifiable when we consider…

Logic · Mathematics 2016-09-07 Wesley Calvert

In 2010, V. Futorny and S. Ovsienko gave a realization of $U(\mathfrak{gl}_n)$ as a subalgebra of the ring of invariants of a certain noncommutative ring with respect to the action of $S_1\times S_2\times\cdots\times S_n$, where $S_j$ is…

Representation Theory · Mathematics 2022-10-31 Erich C. Jauch

The Seiberg-Witten formalism has been realized as an electrodynamics in phase space (associated to the Dirac equation written in phase space) and this fact is explored here with non-abelian gauge group. First, a physically heuristic…

High Energy Physics - Theory · Physics 2019-09-04 J. S. Cruz-Filho , R. G. G. Amorim , F. C. Khanna , A. E. Santana , A. F. Santos , S. C. Ulhoa

We verify a conjecture of Vershik by showing that Hall's universal countable locally finite group can be embedded as a dense subgroup in the isometry group of the Urysohn space and in the automorphism group of the random graph. In fact, we…

Logic · Mathematics 2020-05-05 Mahmood Etedadialiabadi , Su Gao , François Le Maître , Julien Melleray