Toward Vu's conjecture

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Bradshaw, Peter, Dhawan, Abhishek, Methuku, Abhishek, Wigal, Michael C.
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914027020484608
author Bradshaw, Peter
Dhawan, Abhishek
Methuku, Abhishek
Wigal, Michael C.
author_facet Bradshaw, Peter
Dhawan, Abhishek
Methuku, Abhishek
Wigal, Michael C.
contents In 2002, Vu conjectured that graphs of maximum degree $Δ$ and maximum codegree at most $ζΔ$ have chromatic number at most $(ζ+o(1))Δ$. Despite its importance, the conjecture has remained widely open. The only direct progress so far has been obtained in the ``dense regime,'' when $ζ$ is close to $1$, by Hurley, de Verclos, and Kang. In this paper we provide the first progress in the sparse regime $ζ\ll 1$, the case of primary interest to Vu. We show that there exists $ζ_0 > 0$ such that for all $ζ\in [\log^{-32}Δ,ζ_0]$, the following holds: if $G$ is a graph with maximum degree $Δ$ and maximum codegree at most $ζΔ$, then $χ(G) \leq (ζ^{1/32} + o(1))Δ$. We derive this from a more general result that assumes only that the common neighborhood of any $s$ vertices is bounded rather than the codegrees of pairs of vertices. Our more general result also extends to the list coloring setting, which is of independent interest.
format Preprint
id arxiv_https___arxiv_org_abs_2508_16818
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Toward Vu's conjecture
Bradshaw, Peter
Dhawan, Abhishek
Methuku, Abhishek
Wigal, Michael C.
Combinatorics
Discrete Mathematics
In 2002, Vu conjectured that graphs of maximum degree $Δ$ and maximum codegree at most $ζΔ$ have chromatic number at most $(ζ+o(1))Δ$. Despite its importance, the conjecture has remained widely open. The only direct progress so far has been obtained in the ``dense regime,'' when $ζ$ is close to $1$, by Hurley, de Verclos, and Kang. In this paper we provide the first progress in the sparse regime $ζ\ll 1$, the case of primary interest to Vu. We show that there exists $ζ_0 > 0$ such that for all $ζ\in [\log^{-32}Δ,ζ_0]$, the following holds: if $G$ is a graph with maximum degree $Δ$ and maximum codegree at most $ζΔ$, then $χ(G) \leq (ζ^{1/32} + o(1))Δ$. We derive this from a more general result that assumes only that the common neighborhood of any $s$ vertices is bounded rather than the codegrees of pairs of vertices. Our more general result also extends to the list coloring setting, which is of independent interest.
title Toward Vu's conjecture
topic Combinatorics
Discrete Mathematics
url https://arxiv.org/abs/2508.16818