2003/01/30 by Jean-Marc Schlenker
Mathematics · #math.DG #math.MG
published as Discrete and Computational Geometry, 33 (2005):2, 207-221. · 11 pages, 1 image. Revised versions will be posted on http://picard.ups-tlse.fr/~schlenker v2: one statement corrected, ref. added
arxiv created 2003/01/30 · arxiv updated 2009/11/30
Let P be a (non necessarily convex) embedded polyhedron in \R3, with its vertices on an ellipsoid. Suppose that the interior of P can be decomposed into convex polytopes without adding any vertex. Then P is infinitesimally rigid. More generally, let P be a polyhedron bounding a domain which is the union of polytopes C1, ..., Cn with disjoint interiors, whose vertices are the vertices of P. Suppose that there exists an ellipsoid which contains no vertex of P but intersects all the edges of the Ci. Then P is infinitesimally rigid. The proof is based on some geometric properties of hyperideal hyperbolic polyhedra.