English
Related papers

Related papers: Specification for Group Actions on Uniform Spaces

200 papers

We study abstract group actions of locally compact Hausdorff groups on CAT(0) spaces. Under mild assumptions on the action we show that it is continuous or has a global fixed point. This mirrors results by Dudley and Morris-Nickolas for…

Group Theory · Mathematics 2021-02-18 Philip Möller , Olga Varghese

We deal with a set of solutions of the continuous multi-valued dynamical systems on $\mathbb{R}^2$ of the form $\dot x \in F(x)$ where $F(x)$ is a set-valued function and $F=\{f_1,f_2\}$. Such dynamical systems are frequently used in…

Dynamical Systems · Mathematics 2025-09-03 Barbora Volná

Extending and unifying a number of well-known conjectures and open questions, we conjecture that locally elliptic (that is, every element has a bounded orbit) actions by automorphisms of finitely generated groups on finite dimensional…

Group Theory · Mathematics 2025-07-14 Thomas Haettel , Damian Osajda

We prove that all isometric actions of higher rank simple Lie groups and their lattices on arbitrary uniformly convex Banach spaces have a fixed point. This vastly generalises a recent breakthrough of Oppenheim. Combined with earlier work…

Group Theory · Mathematics 2023-03-09 Tim de Laat , Mikael de la Salle

A group action has essential holonomy if the set of points with non-trivial holonomy has positive measure. If such an action is topologically free, then having essential holonomy is equivalent to the action not being essentially free, which…

Dynamical Systems · Mathematics 2023-01-23 Steven Hurder , Olga Lukina

In this paper we study actions of locally compact quantum groups on von Neumann algebras and prove that every action has a canonical unitary implementation, paralleling Haagerup's classical result on the unitary implementation of a locally…

Operator Algebras · Mathematics 2007-05-23 Stefaan Vaes

We prove that finitely generated amenable groups acting on CAT(0) spaces satisfy the following alternative: either every action on a geodesically complete CAT(0) space with bounded geometry (or finite dimension) has a global fixed point, or…

Group Theory · Mathematics 2026-03-30 Hiroyasu Izeki , Ran Ji , Anders Karlsson , Yunhui Wu

We will prove the following theorems. The first theorem posits the existence of a fixed point for the actions of nilpotent Lie groups on nonpositively curved compact manifolds. The second theorem states that actions of solvable Lie groups…

Group Theory · Mathematics 2016-05-18 Mehrzad Monzavi

We present two examples of actions of non-regular locally compact quantum groups on their homogeneous spaces. The homogeneous spaces are defined in a way specific to these examples, but the definitions we use have the advantage of being…

Operator Algebras · Mathematics 2011-04-12 Piotr M. Sołtan

We prove that if two topologically free and entropy regular actions of countable sofic groups on compact metrizable spaces are continuously orbit equivalent, and each group either (i) contains a w-normal amenable subgroup which is neither…

Dynamical Systems · Mathematics 2022-02-23 David Kerr , Hanfeng Li

Actions of locally compact groups and quantum groups on W*-ternary rings of operators are discussed and related crossed products introduced. The results generalise those for von Neumann algebraic actions with proofs based mostly on passing…

Operator Algebras · Mathematics 2017-10-18 Pekka Salmi , Adam Skalski

A group with a geometric action on some hyperbolic space is necessarily word hyperbolic, but on the other hand every countable group acts (metrically) properly by isometries on a locally finite hyperbolic graph. In this paper we consider…

Group Theory · Mathematics 2021-11-29 J. O. Button

We show that algebraic dynamical systems with entropy rank one have uniformly exponentially many periodic points in all directions.

Dynamical Systems · Mathematics 2008-01-14 Richard Miles , Thomas Ward

I give a construction of compact group action on a finite dimensional space Y, whose orbit space is infinite dimensional.

Geometric Topology · Mathematics 2007-05-23 Zhiqing Yang

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 show that every non-precompact topological group admits a fixed point-free continuous action by affine isometries on a suitable Banach space. Thus, precompact groups are defined by the fixed point property for affine isometric actions on…

Group Theory · Mathematics 2008-11-06 Lionel Nguyen Van Thé , Vladimir G. Pestov

In this short note, for countably infinite amenable group actions, we provide topological proofs for the following results: Bowen topological entropy (dimensional entropy) of the whole space equals the usual topological entropy along…

Dynamical Systems · Mathematics 2017-12-19 Dou Dou , Ruifeng Zhang

Let $(X,G)$ be a $G$-action topological system, where $G$ is a countable infinite discrete amenable group and $X$ a compact metric space. In this paper we study the upper capacity entropy and packing entropy for systems with weaker version…

Dynamical Systems · Mathematics 2021-12-15 Xiankun Ren , Wenda Zhang , Yiwei Zhang

In this article, we construct partial periodic quotients of groups which have a non-elementary acylindrical action on a hyperbolic space. In particular, we provide infinite quotients of mapping class groups where a fixed power of every…

Group Theory · Mathematics 2018-08-24 Rémi Coulon

This note records that the Langlands parameter spaces, associated by Adams- Barbasch-Vogan to a real group, may be described as homotopy fixed points (fixed point stacks) of the spaces associated to the corresponding complex group.

Representation Theory · Mathematics 2021-12-14 R. Virk