English
Related papers

Related papers: Groups that act pseudofreely on S^2 x S^2

200 papers

Quasi-free actions of finite groups on Cuntz algebras $\mathcal O_n$ for $n\geq 2$ are classified up to conjugacy by data in the representation ring. Partial results are obtained for quasi-free actions by compact groups.

Operator Algebras · Mathematics 2024-10-11 James Gabe

We classify compact homogeneous geometries of irreducible spherical type and rank at least 2 which admit a transitive action of a compact connected group, up to equivariant 2-coverings. We apply our classification to polar actions on…

Group Theory · Mathematics 2014-04-17 Linus Kramer , Alexander Lytchak

We obtain explicit formulas for the rational homotopy groups of generalised symmetric spaces, i.e., the homogeneous spaces for which the isotropy subgroup appears as the fixed point group of some finite order automorphism of the group. In…

Algebraic Topology · Mathematics 2007-05-23 S. Terzic

We prove that, for p an odd prime, every finite p-group of rank 3 acts freely on a finite complex X homotopy equivalent to a product of three spheres.

Algebraic Topology · Mathematics 2014-10-01 Michele Klaus

In this partly expository monograph we develop a general framework for producing uncountable families of exotic actions of certain classically studied groups acting on the circle. We show that if $L$ is a nontrivial limit group then the…

Geometric Topology · Mathematics 2018-10-05 Sang-hyun Kim , Thomas Koberda , Mahan Mj

Computations based on explicit 4-periodic resolutions are given for the cohomology of the finite groups G known to act freely on S^3, as well as the cohomology rings of the associated 3-manifolds (spherical space forms) M = S^3/G. Chain…

Algebraic Topology · Mathematics 2009-04-14 Satoshi Tomoda , Peter Zvengrowski

We study finite group actions on smooth manifolds of the form $M\#\Sigma$, where $\Sigma$ is an exotic $n$-sphere and $M$ is a closed aspherical space form. We give a classification result for free actions of finite groups on $M\#\Sigma$…

Geometric Topology · Mathematics 2023-03-27 Mauricio Bustamante , Bena Tshishiku

We consider endomorphism actions of arbitrary discrete semigroups on a connected metrizable topological group G. We give necessary and sufficient conditions for expansiveness of such actions when G is a Lie group or a compact…

Dynamical Systems · Mathematics 2007-05-23 Siddhartha Bhattacharya

For group actions on hyperbolic CAT(0) square complexes, we show that the acylindricity of the action is equivalent to a weaker form of acylindricity phrased purely in terms of stabilisers of points, which has the advantage of being much…

Group Theory · Mathematics 2015-09-11 Alexandre Martin

In this paper, we show that if a group acts isometrically on a good hyperbolic space of finite volume entropy through a non-elementary action, then it admits an affine action on some $L^p$ -space with an unbounded orbit for sufficiently…

Group Theory · Mathematics 2025-08-19 Yanlong Hao

We introduce the definition of totally nonfree actions of groups; such actions are naturally related to the theory of characters of groups and their factor-representations of type II. This short note is a brief exposition of a part of a…

Dynamical Systems · Mathematics 2010-12-22 A. Vershik

In this paper we determine all finite groups G that can act on some compact Riemann surface M with the property that if H is any non-trivial subgroup of G, then the orbit surface M/H is the Riemann sphere. The idea is to look at the induced…

Algebraic Geometry · Mathematics 2007-05-23 Sadok Kallel , Denis Sjerve

In this note we derive an upper bound on the number of 2-spheres in the fixed point set of a smooth and homologically trivial cyclic group action of prime order on a simply-connected 4-manifold. This improves the a priori bound which is…

Geometric Topology · Mathematics 2019-03-05 M. J. D. Hamilton

The group theoretical quantization scheme is reconsidered by means of elementary systems. Already the quantization of a particle on a circle shows that the standard procedure has to be supplemented by an additional condition on the…

Quantum Physics · Physics 2016-09-08 Martin Bojowald , Thomas Strobl

Let k be a local field and G the set of k-points of a connected semisimple algebraic k-group of rank one. We describe all torsion-free discrete subgroups of G\times G acting properly discontinuously on G by left and right multiplication. To…

Group Theory · Mathematics 2009-04-20 Fanny Kassel

The shadowable points of dynamical systems has been well-studied by Morales \cite{MR3535492}. This paper aims to generalize the main results obtained by Morales to free semigroup actions. To this end, we introduce the notion of shadowable…

Dynamical Systems · Mathematics 2023-12-25 Ritong Li , Dongkui Ma , Rui Kuang , Xiaojiang Ye

In this paper, we propose a weak version of quotient for the algebraic action of a group on a variety, which we shall call a pseudo-quotient. They arise when we focus on the purely topological properties of good GIT quotients regardless of…

Algebraic Geometry · Mathematics 2023-11-03 Ángel González-Prieto

We prove that a random group has fixed points when it isometrically acts on a CAT(0) cube complex. We do not assume that the action is simplicial.

Metric Geometry · Mathematics 2010-12-21 Koji Fujiwara , Tetsu Toyoda

A scale-multiplicative semigroup in a totally disconnected, locally compact group $G$ is one for which the restriction of the scale function on $G$ is multiplicative. The maximal scale-multiplicative semigroups in groups acting…

Group Theory · Mathematics 2013-12-05 Udo Baumgartner , Jacqui Ramagge , George A. Willis

In this paper, we give a weak classification of locally linear pseudofree actions of the cyclic group of order 3 on a $K3$ surface, and prove the existence of such an action which can not be realized as a smooth action on the standard…

Geometric Topology · Mathematics 2007-06-13 Ximin Liu , Nobuhiro Nakamura