The weak cylinder conjecture for polynomial graphs of bounded degree
Abstract
Ball's weak cylinder conjecture asserts that a set of p2 points in AG(3,p) with at least p non-determined directions is a union of p parallel lines. We prove the conjecture for sets admitting a polynomial graph representation of total degree at most D, provided that p>D9/2. More precisely, a non-cylindrical graph of degree D≥3 satisfies |𝒩S|≤ p+1−⌈ p/(D−1)⌉ under the same hypothesis. This bound is attained when p≡1pmodD−1. The proof relates non-determined directions to permutation polynomials on parallel affine lines. A rigidity lemma for moving line restrictions, together with a reconstruction of their compositional components, bounds the number of contributing directions uniformly in p. Directions with affine restrictions are treated separately; all other contributions are bounded using geometric indecomposability and the Weil bound for plane curves.
Related
- Linear Independence of Polynomial Compositions with Bounded Input Degree
- A bounded degree SDSOS hierarchy for solving SPLD polynomial programs
- Explicit M-polynomial and degree-based topological indices of Hanoi graphs
- A Bounded Degree SOS Plus SONC Hierarchy for Polynomial Optimization
- Upper bounds for ordered Ramsey numbers of forests and bounded-degree graphs
BibTeX
@misc{bartoli2026weak,
title = {{The weak cylinder conjecture for polynomial graphs of bounded degree}},
author = {Daniele Bartoli and Alessandro Giannoni},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.16803},
eprint = {2610.16803},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.16803},
}
RIS
TY - UNPB
TI - The weak cylinder conjecture for polynomial graphs of bounded degree
AU - Daniele Bartoli
AU - Alessandro Giannoni
PY - 2026
DA - 2026/10/12
PB - arXiv
DO - 10.48550/arxiv.2610.16803
UR - https://arxiv.org/abs/2610.16803
AB - Ball's weak cylinder conjecture asserts that a set of p^2 points in AG(3,p) with at least p non-determined directions is a union of p parallel lines. We prove the conjecture for sets admitting a polynomial graph representation of total degree at most D, provided that p>D^9/2. More precisely, a non-cylindrical graph of degree D≥3 satisfies |𝒩_S|≤ p+1−⌈ p/(D−1)⌉ under the same hypothesis. This bound is attained when p≡1pmodD−1. The proof relates non-determined directions to permutation polynomials on parallel affine lines. A rigidity lemma for moving line restrictions, together with a reconstruction of their compositional components, bounds the number of contributing directions uniformly in p. Directions with affine restrictions are treated separately; all other contributions are bounded using geometric indecomposability and the Weil bound for plane curves.
ER -