face map

1. Definition

Let \(\Delta\) be the simplex category. Then the \(i\)-th face map is defined as monotone map

\begin{align*} \partial^i: [k] \rightarrow& [k+1] \\ j \mapsto& \begin{cases} j & \mbox{if } j < i \\ j + 1 & \mbox{else } \\ \end{cases} \end{align*}

Date: nil

Author: Anton Zakrewski

Created: 2024-10-13 So 18:27