--- date: 2022-02-23 18:45 modification date: Wednesday 23rd February 2022 18:45:08 title: "Freudenthal suspension" aliases: [Freudenthal suspension theorem, Freudenthal suspension] --- Last modified date: <%+ tp.file.last_modified_date() %> --- - Tags - #homotopy - Refs: - #todo/add-references - Links: - #todo/create-links --- # Freudenthal Suspension Theorem ![](attachments/Pasted%20image%2020220403205623.png) ![](attachments/Pasted%20image%2020220403205640.png) If $X$ is an $n\dash$ connected CW complex, then there are maps $\pi_i X \to \pi_{i+1} \Sigma X$ which is an isomorphism for $i\leq 2n$ and a surjection for $i=2n+1$. # Examples ![](attachments/Pasted%20image%2020220403205705.png)