Realizations of the Associahedron and Cyclohedron

نویسندگان

  • Christophe Hohlweg
  • Carsten E. M. C. Lange
چکیده

We describe many different realizations with integer coordinates for the associahedron (i.e. the Stasheff polytope) and for the cyclohedron (i.e. the Bott-Taubes polytope) and compare them to the permutahedron of type A and B respectively. The coordinates are obtained by an algorithm which uses an oriented Coxeter graph of type An or Bn respectively as only input and which specialises to a procedure presented by J.-L. Loday for a certain orientation of An. The described realizations have cambrian fans of type A and B as normal fan. This settles a conjecture of N. Reading for cambrian lattices of these types.

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عنوان ژورنال:
  • Discrete & Computational Geometry

دوره 37  شماره 

صفحات  -

تاریخ انتشار 2007