English

The totally nonnegative Grassmannian is a ball

Combinatorics 2022-06-08 v3 High Energy Physics - Theory Geometric Topology

Abstract

We prove that three spaces of importance in topological combinatorics are homeomorphic to closed balls: the totally nonnegative Grassmannian, the compactification of the space of electrical networks, and the cyclically symmetric amplituhedron.

Keywords

Cite

@article{arxiv.1707.02010,
  title  = {The totally nonnegative Grassmannian is a ball},
  author = {Pavel Galashin and Steven N. Karp and Thomas Lam},
  journal= {arXiv preprint arXiv:1707.02010},
  year   = {2022}
}

Comments

19 pages. v2: Exposition improved in many places. v3: Final version

R2 v1 2026-06-22T20:40:16.428Z