A remarkable result of Shemer [7] states that the combinatorial structure of a neighbourly 2mpolytope determines the combinatorial structure of each of its subpolytopes. From this, it follows that every subpolytope of a cyclic 2m-polytope is cyclic. In this note, we present a direct proof of this co
On Subdivision Posets of Cyclic Polytopes
✍ Scribed by Paul H. Edelman; Jörg Rambau; Victor Reiner
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 231 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0195-6698
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✦ Synopsis
There are two related poset structures, the higher Stasheff-Tamari orders, on the set of all triangulations of the cyclic d polytope with n vertices. In this paper it is shown that both of them have the homotopy type of a sphere of dimension nd -3.
Moreover, we resolve positively a new special case of the Generalized Baues Problem: the Baues poset of all polytopal decompositions of a cyclic polytope of dimension d ≤ 3 has the homotopy type of a sphere of dimension nd -2.
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