Jie Ma

activity

20242026

collaborators

9 papers

math.CO2026

Longest cycles and Dirac-type results in highly connected graphs

Jie Ma, Bo Ning, Ziyuan Zhao

A classical theorem of Nash-Williams states that if $G$ is a $2$ -connected graph on $n$ vertices with minimum degree at least $(n + 2) /3$ , then for every longest cycle $C$ of $G$ , th…

math.CO2026

Almost Affine Invariance Over Prime Fields: Green Problem 90

Jie Ma, Quanyu Tang, Max Wenqiang Xu

Let $A \subset F_{p}$ with density 1/2. We call a set $A$ almost affine invariant under an affine transformation $ϕ (x) = a x + b$ if \[|A \triangle ϕ(A)| =o(p).\] We determine tha…

math.CO2026

On Spielman's Laplacian Eigenratio Conjecture and Related Problems

Jie Ma, Quanyu Tang, Yuchang Wang +1

Let $G$ be an $n$ -vertex graph with Laplacian eigenvalues $0 = λ_{1} (G) \leq λ_{2} (G) \leq \dots \leq λ_{n} (G)$ . Motivated by the Alon-Boppana bound and the Ramanujan phenomenon for regular grap…

math.CO2026

Hypergraphs without Subgraphs of Given Connectivity

Jie Ma, Shengjie Xie, Zhiheng Zheng

In this paper, we study the problem of determining the maximum number $F_{r} (n, k)$ of edges in an $n$ -vertex $r$ -uniform hypergraph that contains no $(k + 1)$ -connected subgraph. The g…

math.CO2026

On a maximal anti-Ramsey conjecture of Burr, Erdős, Graham, and Sós

Matija Bucic, Kaizhe Chen, Jie Ma

Given a graph $H$ , the maximal anti-Ramsey function $f (n, e, H)$ denotes the minimum integer $f$ for which there exists an $n$ -vertex graph $G$ with at least $e$ edges admitting an e…

math.CO2026

Largest Sidon subsets in weak Sidon sets

Jie Ma, Quanyu Tang

A finite set $S \subset R$ is called a Sidon set if all sums $x + y$ with $x, y \in S$ and $x \leq y$ are distinct, and a weak Sidon set if all sums $x + y$ with $ x,y…

math.CO2026

Towards the Erdős matching conjecture for 4-uniform hypergraphs: stability and applications

Peter Frankl, Hongliang Lu, Jie Ma +1

A famous conjecture of Erdős asserts that for $k \geq 3$ , the maximum number of edges in an $n$ -vertex $k$ -uniform hypergraph without $s + 1$ pairwise disjoint edges is $\max\{\binom{n…

math.CO2025

An exponential improvement for Ramsey lower bounds

Jie Ma, Wujie Shen, Shengjie Xie

We prove a new lower bound on the Ramsey number $r (ℓ, C ℓ)$ for any constant $C > 1$ and sufficiently large $ℓ$ , showing that there exists $ε = ε (C) > 0$ s…

math.CO2024

Discrepancies of perfect matchings in hypergraphs

Hongliang Lu, Jie Ma, Shengjie Xie

In this paper, we determine the minimum degree threshold of perfect matchings with high discrepancy in $r$ -edge-colored $k$ -uniform hypergraphs for all $k \geq 3$ and $r \geq 2$ , the…