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Related papers: A note on automatic continuity

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In this paper we focus on the set-open topologies on the group $\mathcal{H}(X)$ of all self-homeomorphisms of a topological space $X$ which yield continuity of both the group operations, product and inverse function. As a consequence, we…

General Topology · Mathematics 2020-02-20 Alexander V. Osipov

We obtain analogues of classical results on automorphism groups of holomorphic fiber bundles, in the setting of group schemes. Also, we establish a lifting property of the connected automorphism group, for torsors under abelian varieties.…

Algebraic Geometry · Mathematics 2011-06-30 Michel Brion

We describe the development of the theory of automatic groups. We begin with a historical introduction, define the concepts of automatic, biautomatic and combable groups, derive basic properties, then explain how hyperbolic groups and the…

Group Theory · Mathematics 2022-05-31 Sarah Rees

We show that every automorphism $\alpha$ of a free group $F_k$ of finite rank $k$ has {\it asymptotically periodic} dynamics on $F_k$ and its boundary $\partial F_k$: there exists a positive power $\alpha^q$ such that every element of the…

Group Theory · Mathematics 2008-10-06 Gilbert Levitt , Martin Lustig

We prove a new kind of homological stability theorem for automorphism groups of finitely-generated projective modules over Dedekind domains, which takes into account all possible stabilisation maps between these, rather than only…

Commutative Algebra · Mathematics 2024-05-14 Oscar Randal-Williams

We obtain a homological characterisation of virtually free-by-cyclic groups among groups that are hyperbolic and virtually compact special. As a consequence, we show that many groups known to be coherent actually possess the stronger…

Group Theory · Mathematics 2024-06-28 Dawid Kielak , Marco Linton

In this paper we explore the extent to which the algebraic structure of a monoid $M$ determines the topologies on $M$ that are compatible with its multiplication. Specifically we study the notions of automatic continuity; minimal Hausdorff…

Rings and Algebras · Mathematics 2024-05-29 L. Elliott , J. Jonušas , Z. Mesyan , J. D. Mitchell , M. Morayne , Y. Péresse

We show that the isomorphism problem is solvable in the class of central extensions of word-hyperbolic groups, and that the isomorphism problem for biautomatic groups reduces to that for biautomatic groups with finite centre. We describe an…

Geometric Topology · Mathematics 2015-05-27 Martin R. Bridson , Lawrence Reeves

The homology groups of the automorphism group of a free group are known to stabilize as the number of generators of the free group goes to infinity, and this paper relativizes this result to a family of groups that can be defined in terms…

Geometric Topology · Mathematics 2014-11-11 Allen Hatcher , Nathalie Wahl

We classify all group topologies coarser than the topology of stabilizers of finite sets in the case of automorphism groups of countable free-homogeneous structures, Urysohn space and Urysohn sphere, among other related results.

Logic · Mathematics 2024-02-21 Zaniar Ghadernezhad , Javier de la Nuez González

We show that every abstract homomorphism $\varphi$ from a locally compact group $L$ to a graph product $G_\Gamma$, endowed with the discrete topology, is either continuous or $\varphi(L)$ lies in a 'small' parabolic subgroup. In particular,…

Group Theory · Mathematics 2019-08-14 Linus Kramer , Olga Varghese

The automorphisms of a two-generator free group acting on the space of orientation-preserving isometric actions of on hyperbolic 3-space defines a dynamical system. Those actions which preserve a hyperbolic plane but not an orientation on…

Dynamical Systems · Mathematics 2016-10-11 William Goldman , Greg McShane , George Stantchev , Ser Peow Tan

We investigate fixed-point properties of automorphisms of groups similar to R. Thompson's group $F$. Revisiting work of Gon\c{c}alves-Kochloukova, we deduce a cohomological criterion to detect infinite fixed-point sets in the…

Classical theorems from the early 20th century state that any Haar measurable homomorphism between locally compact groups is continuous. In particular, any Lebesgue-measurable homomorphism $\phi:\mathbb{R} \to \mathbb{R}$ is of the form…

Geometric Topology · Mathematics 2024-09-05 Tom Meyerovitch , Omri Nisan Solan

We show that the automorphism group of Philip Hall's universal locally finite group has ample generics,that is, it admits comeager diagonal conjugacy classes in all dimensions.Consequently, it has the small index property, is not the union…

Logic · Mathematics 2017-10-23 Shichang Song

Given a Baumslag-Solitar group, we study its space of subgroups from a topological and dynamical perspective. We first determine its perfect kernel (the largest closed subset without isolated points). We then bring to light a natural…

Group Theory · Mathematics 2024-11-11 Alessandro Carderi , Damien Gaboriau , François Le Maître , Yves Stalder

Transformation monoids carry a canonical topology --- the topology of point-wise convergence. A closed transformation monoid $\mathfrak{M}$ is said to have automatic homeomorphicity with respect to a class $\mathcal{K}$ of structures, if…

Logic · Mathematics 2017-04-04 Christian Pech , Maja Pech

It is a well-known fact that every group $G$ has a presentation of the form $G = F/R$, where $F$ is a free group and $R$ the kernel of the natural epimorphism from $F$ onto $G$. Driven by the desire to obtain a similar presentation of the…

Group Theory · Mathematics 2009-10-31 Vladimir Shpilrain

In this note, we provide a description of the structure of homomorphisms from a finitely generated group to any torsion-free (3-dimensional) Kleinian group with uniformly bounded finite covolume. This is analogous to the Jorgensen-Thurston…

Geometric Topology · Mathematics 2014-10-01 Yi Liu

Given an ample groupoid, we construct a spectral sequence with groupoid homology with integer coefficients on the second sheet, converging to the K-groups of the (reduced) groupoid C*-algebra, provided the groupoid has torsion-free…

K-Theory and Homology · Mathematics 2022-07-12 Valerio Proietti , Makoto Yamashita