English

Counting geodesics between surface triangulations

Geometric Topology 2025-03-19 v1 Computational Geometry Combinatorics

Abstract

Given a surface Σ\Sigma equipped with a set PP of marked points, we consider the triangulations of Σ\Sigma with vertex set PP. The flip-graph of Σ\Sigma whose vertices are these triangulations, and whose edges correspond to flipping arcs appears in the study of moduli spaces and mapping class groups. We consider the number of geodesics in the flip-graph of Σ\Sigma between two triangulations as a function of their distance. We show that this number grows exponentially provided the surface has enough topology, and that in the remaining cases the growth is polynomial.

Keywords

Cite

@article{arxiv.2308.05688,
  title  = {Counting geodesics between surface triangulations},
  author = {Hugo Parlier and Lionel Pournin},
  journal= {arXiv preprint arXiv:2308.05688},
  year   = {2025}
}

Comments

26 pages, 7 figures

R2 v1 2026-06-28T11:52:58.991Z