# Kerodon

$\Newextarrow{\xRightarrow}{5,5}{0x21D2}$ $\newcommand\empty{}$

Remark 2.5.9.14. Lemma 2.5.9.13 is a homological incarnation of the following topological assertion: the geometric realization $| \operatorname{\raise {0.1ex}{\square }}^{I} | \simeq [0,1]^{I}$ is a manifold, whose boundary can be written as a union of the faces $\{ 0\} \times [0,1]^{I \setminus \{ i\} }$ and $\{ 1\} \times [0,1]^{I \setminus \{ i\} }$.