English

Cyclohedron and Kantorovich-Rubinstein polytopes

Combinatorics 2018-04-20 v3

Abstract

We show that the cyclohedron (Bott-Taubes polytope) WnW_n arises as the dual of a Kantorovich-Rubinstein polytope KR(ρ)KR(\rho), where ρ\rho is a quasi-metric (asymmetric distance function) satisfying strict triangle inequality. From a broader perspective, this phenomenon illustrates the relationship between a nestohedron ΔF^\Delta_{\mathcal{\widehat{F}}} (associated to a building set F^\mathcal{\widehat{F}}) and its non-simple deformation ΔF\Delta_{\mathcal{F}}, where F\mathcal{F} is an `irredundant' or `tight basis' of F^\mathcal{\widehat{F}}. Among the consequences are a new proof of a recent result of Gordon and Petrov (arXiv:1608.06848 [math.CO]) about ff-vectors of generic Kantorovich-Rubinstein polytopes and an extension of a theorem of Gelfand, Graev, and Postnikov, about triangulations of the type A, positive root polytopes.

Keywords

Cite

@article{arxiv.1703.06612,
  title  = {Cyclohedron and Kantorovich-Rubinstein polytopes},
  author = {Filip D. Jevtić and Marija Jelić and Rade T. Živaljević},
  journal= {arXiv preprint arXiv:1703.06612},
  year   = {2018}
}

Comments

Improved exposition; added Section 6 (Alternative approaches and proofs)