nLab
homotopy sphere

Contents

Context

Spheres

Homotopy theory

homotopy theory, (∞,1)-category theory, homotopy type theory

flavors: stable, equivariant, rational, p-adic, proper, geometric, cohesive, directed

models: topological, simplicial, localic, …

see also algebraic topology

Introductions

Definitions

Paths and cylinders

Homotopy groups

Basic facts

Theorems

Contents

Idea

A homotopy sphere is a topological space which need not be homeomorphic to an n-sphere, but which has the same homotopy type as an nn-sphere.

Properties

Redirects

References

  • Laurent Siebenmann, Topological Poincaré conjecture in dimension 4 (the work of M. H. Freedman) (pdf)

Last revised on December 1, 2019 at 14:12:35. See the history of this page for a list of all contributions to it.