Discrete & Computational Geometry

, Volume 46, Issue 1, pp 100–131 | Cite as

Prodsimplicial-Neighborly Polytopes

  • Benjamin Matschke
  • Julian Pfeifle
  • Vincent PilaudEmail author


Simultaneously generalizing both neighborly and neighborly cubical polytopes, we introduce PSN polytopes: their k-skeleton is combinatorially equivalent to that of a product of r simplices.

We construct PSN polytopes by three different methods, the most versatile of which is an extension of Sanyal & Ziegler’s “projecting deformed products” construction to products of arbitrary simple polytopes. For general r and k, the lowest dimension we achieve is 2k+r+1.

Using topological obstructions similar to those introduced by Sanyal to bound the number of vertices of Minkowski sums, we show that this dimension is minimal if we additionally require that the PSN polytope is obtained as a projection of a polytope that is combinatorially equivalent to the product of r simplices, when the dimensions of these simplices are all large compared to k.


Neighborly polytope Product of simplices Skeleta preserving projection 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Benjamin Matschke
    • 1
  • Julian Pfeifle
    • 2
  • Vincent Pilaud
    • 3
    Email author
  1. 1.Technische Universität BerlinBerlinGermany
  2. 2.Departament de Matemàtica Aplicada IIUniversitat Politècnica de CatalunyaBarcelonaSpain
  3. 3.Équipe Combinatoire et OptimisationUniversité Pierre et Marie CurieParisFrance

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