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A natural pseudometric on homotopy groups of metric spaces

Published online by Cambridge University Press:  08 November 2023

Jeremy Brazas*
Affiliation:
West Chester University, 25 University Avenue, West Chester, PA 19383, United States of America
Paul Fabel
Affiliation:
Mississippi State University, 410 Allen Hall, 175 President’s Circle, Mississippi State, MS, 39762, United States of America
*
Corresponding author: Jeremy Brazas; Email: jbrazas@wcupa.edu

Abstract

For a path-connected metric space $(X,d)$, the $n$-th homotopy group $\pi _n(X)$ inherits a natural pseudometric from the $n$-th iterated loop space with the uniform metric. This pseudometric gives $\pi _n(X)$ the structure of a topological group, and when $X$ is compact, the induced pseudometric topology is independent of the metric $d$. In this paper, we study the properties of this pseudometric and how it relates to previously studied structures on $\pi _n(X)$. Our main result is that the pseudometric topology agrees with the shape topology on $\pi _n(X)$ if $X$ is compact and $LC^{n-1}$ or if $X$ is an inverse limit of finite polyhedra with retraction bonding maps.

Type
Research Article
Copyright
© The Author(s), 2023. Published by Cambridge University Press on behalf of Glasgow Mathematical Journal Trust

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