English
Related papers

Related papers: Extending Group Actions

200 papers

Actions of a locally compact group G on a measure space X give rise to unitary representations of G on Hilbert spaces. We review results on the rigidity of these actions from the spectral point of view, that is, results about the existence…

Group Theory · Mathematics 2016-05-12 Bachir Bekka

We presented a Hilbert-Mumford criterion for polystablility associated with an action of a real reductive Lie group $G$ on a real submanifold $X$ of a Kahler manifold $Z$. Suppose the action of a compact Lie group with Lie algebra…

Differential Geometry · Mathematics 2025-03-05 Leonardo Biliotti , Oluwagbenga Joshua Windare

In this paper we study chaotic behavior of actions of a countable discrete group acting on a compact metric space by self-homeomorphisms. For actions of a countable discrete group G, we introduce local weak mixing and Li-Yorke chaos; and…

Dynamical Systems · Mathematics 2015-03-10 Zhaolong Wang , Guohua Zhang

In this talk, we'll present some recent results related to group actions in several complex variables. We'll not aim at giving a complete survey about the topic but giving some our own results and related ones. We'll divide the results into…

Complex Variables · Mathematics 2007-05-23 Xiangyu Zhou

In this short note, we study the bordism problem for group actions on the torus and give examples of groups acting on the torus by diffeomorphisms isotopic to the identity that cannot be extended to an action on a bounding 3-manifold. This…

Geometric Topology · Mathematics 2021-05-10 Kathryn Mann , Sam Nariman

If a Hausdorff locally compact paracompact space has a coarse structure, then there is a family of well behaved compactifications associated to it. If there are two of these spaces, $X$ and $Y$, with a good coarse equivalence, then there is…

General Topology · Mathematics 2022-08-02 Lucas H. R. de Souza

For every compact, connected manifold $M$, we prove the existence of a sentence $\phi_M$ in the language of groups such that the homeomorphism group of another compact manifold $N$ satisfies $\phi_M$ if and only if $N$ is homeomorphic to…

Group Theory · Mathematics 2025-03-12 Sang-hyun Kim , Thomas Koberda , J. de la Nuez González

This paper deals with the extension of partial actions of topological groups on topological spaces. Within this framework, we introduce a class of topological embeddings defined via the inverse semigroup of homeomorphisms between open…

General Topology · Mathematics 2026-04-17 Luis A. Martínez-Sánchez , Héctor Pinedo , José L. Vilca-Rodríguez

We prove results toward classifying compact Lorentz manifolds on which Heisenberg groups act isometrically. We give a general construction, leading to a new example, of codimension-one actions--those for which the dimension of the…

Differential Geometry · Mathematics 2007-05-23 Karin Melnick

We show that if a 1-ended group $G$ acts geometrically on a CAT(0) space $X$ and $\bd X$ is separated by $m$ points then either $G$ is virtually a surface group or $G$ splits over a 2-ended group. In the course of the proof we study nesting…

Group Theory · Mathematics 2018-07-12 Panos Papasoglu , Eric Swenson

In this paper, we consider minimal group actions of countable groups on compact Hausdorff spaces by homeomorphisms. We show that the existence of a point with finite stabilizer imposes strong restrictions on the dynamics: the residual set…

Dynamical Systems · Mathematics 2026-05-15 María Isabel Cortez , Maik Gröger , Olga Lukina

We raise the question of realizability of group actions which is an extended version of the 1960's Kahn realizability problem for (abstract) groups. Namely, if $M$ is a $\mathbb ZG$-module for a group $G$, we say that a simply-connected…

Algebraic Topology · Mathematics 2015-11-20 Cristina Costoya , Antonio Viruel

We generalize the dual notions of "expansion" and "collapse" so they can be applied to arbitrary metric spaces. We also expand the theory to allow for infinitely many such moves. Those tools are then employed to prove a variety of…

Geometric Topology · Mathematics 2023-11-07 Craig R. Guilbault , Daniel Gulbrandsen

We show that on a totally disconnected compact metric space every separating homeomorphisms is expansive except at periodic points. We conclude that minimal separating homeomorphisms are expansive and that every separating homeomorphism has…

Dynamical Systems · Mathematics 2017-07-21 Alfonso Artigue

We study the group of almost-periodic homeomorphisms of the real line. Our main result states that an action of a finitely generated group on the real line without global fixed point is conjugated to an almost-periodic action without almost…

Group Theory · Mathematics 2011-02-23 Bertrand Deroin

We prove that every topological action of a countable group on a metrizable space can be realized as a bi-Lipschitz action with respect to some compatible metric. This extends a result due to U. Hamenst\"{a}dt regarding finitely generated…

Group Theory · Mathematics 2024-10-11 Inhyeok Choi , Sang-hyun Kim

We show that a class of ergodic transformations on a probability measure space $(X,\mu)$ extends to a representation of $\mathcal{B}(L^2(X,\mu))$ that is both implemented by a Cuntz family and ergodic. This class contains several known…

Operator Algebras · Mathematics 2018-08-17 Evgenios T. A. Kakariadis , Justin R. Peters

Let M be a compact manifold. We show the identity component $\mathrm{Homeo}_0(M)$ of the group of self-homeomorphisms of M has a well-defined quasi-isometry type, and study its large scale geometry. Through examples, we relate this large…

Geometric Topology · Mathematics 2016-07-08 Kathryn Mann , Christian Rosendal

Let a countable amenable group $G$ act on a \zd\ compact metric space $X$. For two clopen subsets $\mathsf A$ and $\mathsf B$ of $X$ we say that $\mathsf A$ is \emph{subequivalent} to $\mathsf B$ (we write $\mathsf A\preccurlyeq \mathsf…

Dynamical Systems · Mathematics 2020-09-29 Tomasz Downarowicz , Guohua Zhang

We study holomorphic extensions of one-parameter groups on locally convex spaces with a view to applications to KMS boundary conditions. In the first part we deal with analytic extensions of one-parameter groups of operators on locally…

Representation Theory · Mathematics 2023-09-19 Daniel Beltita , Karl-Hermann Neeb