Positive Lin-Lu-Yau curvature, planar graphs, and forbidden minors
Abstract
Over the past few decades, several notions of graph curvature have been introduced. Among them, Ollivier curvature, defined through optimal transport, and its Lin--Lu--Yau variant provide notions of curvature for graphs which retain several features of their counterpart in Riemannian geometry. A classical problem in this context is to understand the global structure of positively curved spaces. Lu and Wang proved that there are only finitely many positively curved planar graphs of minimum degree at least 3. In this paper, we study two directions motivated by this result. We first show that for fixed 2≤ s≤ t, there are only finitely many positively curved Ks,t-minor-free graphs with minimum degree at least s. In particular, this generalizes the result of Lu and Wang to graphs embeddable on any fixed surface. We then give a complete classification of positively curved 5-connected plane triangulations. In particular, we show that there are only five examples, on 12, 14, 15, 16, and 17 vertices.
Related
- Entropy estimates and volume rigidity for graphs with positive Bakry-Émery curvature
- On the classification of regular graphs with positive Lin-Lu-Yau curvature
- On the maximum degree and order of Kt-minor-free graphs with positive Lin--Lu--Yau curvature
- Strong isometric path complexity of graphs: Asymptotic minors, restricted holes, and graph operations
- A finite forbidden family with superlinear surplus and non-join extremal graphs
BibTeX
@misc{esperet2026positive,
title = {{Positive Lin-Lu-Yau curvature, planar graphs, and forbidden minors}},
author = {Louis Esperet and Julie Semaan},
howpublished = {HAL},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.10307},
eprint = {2610.10307},
archivePrefix = {arXiv},
url = {https://hal.science/hal-05785352v1},
}
RIS
TY - UNPB
TI - Positive Lin-Lu-Yau curvature, planar graphs, and forbidden minors
AU - Louis Esperet
AU - Julie Semaan
PY - 2026
DA - 2026/10/07
PB - HAL
DO - 10.48550/arxiv.2610.10307
UR - https://hal.science/hal-05785352v1
AB - Over the past few decades, several notions of graph curvature have been introduced. Among them, Ollivier curvature, defined through optimal transport, and its Lin--Lu--Yau variant provide notions of curvature for graphs which retain several features of their counterpart in Riemannian geometry. A classical problem in this context is to understand the global structure of positively curved spaces. Lu and Wang proved that there are only finitely many positively curved planar graphs of minimum degree at least 3. In this paper, we study two directions motivated by this result. We first show that for fixed 2≤ s≤ t, there are only finitely many positively curved K_s,t-minor-free graphs with minimum degree at least s. In particular, this generalizes the result of Lu and Wang to graphs embeddable on any fixed surface. We then give a complete classification of positively curved 5-connected plane triangulations. In particular, we show that there are only five examples, on 12, 14, 15, 16, and 17 vertices.
ER -