The six-dimensional Delaunay polytopes

The six-dimensional Delaunay polytopes

Given a lattice L, a full dimensional polytope P is called a Delaunay polytope if the set of its vertices is S ∩ L with S being an empty sphere of the lattice. Extending our previous work [DD01] on the hypermetric cone HY P7, we classify the six-dimensional Delaunay polytopes according to their combinatorial type. The list of 6241 combinatorial types is obtained by a study of the set of faces o...

Inscribable polytopes via Delaunay triangulations

Delaunay polytopes of cut lattices

We continue 3], the study of the lattice L n generated by cuts of the complete graph on a set V n of n vertices. The lattice L n spans an N = ? n 2-dimensional space of all functions deened on a set V 2 n of all unordered pairs of the set V n. We prove that the cut polytope, i.e. the convex hull of all cuts, is an asymmetric Delaunay polytope of L n. Symmetric Delaunay polytopes of a lattice L ...

Neighborly inscribed polytopes and Delaunay triangulations

We prove that there are superexponentially many combinatorially distinct d-dimensional neighborly Delaunay triangulations on n points. These are the first examples of neighborly Delaunay triangulations that cannot be obtained via a stereographic projection of an inscribed cyclic polytope, and provide the current best lower bound for the number of combinatorial types of Delaunay triangulations. ...

Perfect Delaunay Polytopes and Perfect Inhomogeneous Forms

A lattice Delaunay polytope D is called perfect if it has the property that there is a unique circumscribing ellipsoid with interior free of lattice points, and with the surface containing only those lattice points that are the vertices of D. An inhomogeneous quadratic form is called perfect if it is determined by such a circumscribing ”empty ellipsoid” uniquely up to a scale factorComplete pro...