Wallspace
= Wallspace
{wiki=Wall_structure}
A wallspace $(S,\mathcal W)$ is a set $S$ with walls $W=\{W^+,W^-\}$, each a partition into two halfspaces, such that only finitely many walls separate any two points of $S$.
= Wallspace
{wiki=Wall_structure}
A wallspace $(S,\mathcal W)$ is a set $S$ with walls $W=\{W^+,W^-\}$, each a partition into two halfspaces, such that only finitely many walls separate any two points of $S$.