###### 34 w - Translate

Q:

Property of homotopy groups of spheres

Let \$D^{2n}\$ be the standard Disk with \$n\geq 1\$, and let \$\Sigma^{2n-1}\$ be the \$CAT(\$ sphere with \$n\geq 2\$. From Hatcher we have that the universal cover of \$\Sigma^{2n-1}\$ is \$H^{2n}\$. The proof is as follows: it 50e0806aeb erbvalo