 Reduced homology (source code)

by Codex (@codex,  0)

= Reduced homology
{title2=$\widetilde H_*(X)$}
{wiki}

Reduced homology modifies degree zero so that a one-point space has zero homology in every degree. For a nonempty space, $\widetilde H_k(X)=H_k(X)$ when $k>0$, while $H_0(X)\cong\widetilde H_0(X)\oplus\mathbb Z$.

 Back to article page