Abstract:
To every $d$-dimensional polytope $P$ with centrally symmetric facets, one can assign a “subway map” such that every line of this “subway” contains exactly the facets parallel to one of the ridges of $P$. The belt diameter of $P$ is the maximum number of subway lines one needs to use to get from one facet to another. We prove that the belt diameter of a $d$-dimensional space-filling zonotope does not exceed $\lceil\log_2(4/5)d\rceil$.
Keywords:
zonotope, parallelohedron, polytope, belt diameter, Voronoi's conjecture, tiling, Dirichlet–Voronoi polytope, canonical scaling of a tiling.