Jordan property for homeomorphism groups and almost fixed point property

We study properties of continuous finite group actions on topological manifolds that hold true, for any finite group action, after possibly passing to a subgroup of index bounded above by a constant depending only on the manifold. These include the Jordan property, the almost fixed point property, a...

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Detalles Bibliográficos
Autor: Mundet i Riera, Ignasi
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/216598
Acceso en línea:https://hdl.handle.net/2445/216598
Access Level:acceso abierto
Palabra clave:Grups de transformacions
Topologia algebraica
Grups finits
Transformation groups
Algebraic topology
Finite groups
Descripción
Sumario:We study properties of continuous finite group actions on topological manifolds that hold true, for any finite group action, after possibly passing to a subgroup of index bounded above by a constant depending only on the manifold. These include the Jordan property, the almost fixed point property, as well as bounds on the discrete degree of symmetry. Most of our results apply to manifolds satisfying some restriction such as having nonzero Euler characteristic or having the integral homology of a sphere. For an arbitrary topological manifold $X$ such that $H_*(X ; \mathbb{Z})$ is finitely generated, we prove the existence of a constant $C$ with the property that for any continuous action of a finite group $G$ on $X$ such that every $g \in G$ fixes at least one point of $X$, there is a subgroup $H \leq G$ satisfying $[G: H] \leq C$ and a point $x \in X$ which is fixed by all elements of $H$.