Capturing Polytopal Symmetries by Coloring the Edge-Graph

Abstract

A general (convex) polytope $P\subset {\mathbb{R}}^d$ and its edge-graph $G_P$ can have very distinct symmetry properties. We construct a coloring (of the vertices and edges) of the edge-graph so that the combinatorial symmetry group of the colored edge-graph is isomorphic (in a natural way) to ${\mathrm{Aut}}_{\mathrm{GL}}(P)$, the group of linear symmetries of the polytope. We also construct an analogous coloring for ${\mathrm{Aut}}_{\mathrm{O}}(P)$, the group of orthogonal symmetries of $P$.