English

Extension complexity and realization spaces of hypersimplices

Metric Geometry 2017-02-28 v2 Combinatorics

Abstract

The (n,k)-hypersimplex is the convex hull of all 0/1-vectors of length n with coordinate sum k. We explicitly determine the extension complexity of all hypersimplices as well as of certain classes of combinatorial hypersimplices. To that end, we investigate the projective realization spaces of hypersimplices and their (refined) rectangle covering numbers. Our proofs combine ideas from geometry and combinatorics and are partly computer assisted.

Keywords

Cite

@article{arxiv.1601.02416,
  title  = {Extension complexity and realization spaces of hypersimplices},
  author = {Francesco Grande and Arnau Padrol and Raman Sanyal},
  journal= {arXiv preprint arXiv:1601.02416},
  year   = {2017}
}

Comments

17 pages, 3 figures, 2 python scripts as part of the submission; v2: Rectangle covering number bounds improved (following suggestion of the referees), Results added on prescribability of facets of combinatorial hypersimplices, minor fixes

R2 v1 2026-06-22T12:26:43.791Z