Yi-Zheng Fan

activity

20222026

most citedLinear spectral Turan problems for expansions of graphs with given chromatic number

4 citations · 7 across the 14 of their papers we have counts for

collaborators

14 papers

math.CO2026

Tensor Spectral Stability for Uniform Hypergraphs with Bounded Matching Number

Yi Xu, Yi-Zheng Fan

We establish a tensor spectral stability theorem for uniform hypergraphs with bounded matching number. More precisely, for fixed integers $k \geq 3$ and $β \geq 2$ , and sufficiently l…

math.CO2026

Degree Majorization and Laplacian Eigenvalue Sums for Simplicial Complexes

Huan-Zhi Zhang, Yi-Min Song, Yi-Zheng Fan

Let $K$ be an $r$ -dimensional simplicial complex. We prove that the spectrum of its $(r - 1)$ -dimensional up-Laplacian is majorized by the conjugate degree sequence of its $(r - 1)…

math.CO2026

Signless Laplacian Spectral Radius and Link Homology of Simplicial Complexes

Yi-Zheng Fan, Huan-Zhi Zhang

In this paper, we study the signless Laplacian spectral radius of pure simplicial complexes under local homological restrictions on links. Let $K$ be a pure $r$ -dimensional complex…

math.CO2026

Upper Bounds for the Largest Laplacian Eigenvalue of Simplicial Complexes

Huan-Zhi Zhang, Yi-Zheng Fan

Let $K$ be a finite $r$ -dimensional simplicial complex with vertex set $V$ of size $n$ . We study the largest eigenvalue of the combinatorial $(r - 1)$ -up Laplacian $L^{\operatorname{…

math.CO2026

Orthogonal degree-similarity of edge-deleted strongly regular graphs

Yi-Zheng Fan, Wei Wang, Kuo Zhang

Godsil and Sun asked whether, for a strongly regular graph $X$ and any two different edges $e$ and $f$ , the edge-deleted graphs $X ∖ e$ and $X ∖ f$ are degree-similar…

math.CO2026

Smith normal forms for coalescences at cospectral vertices

Yi-Zheng Fan, Kuo Zhang, Wei Wang

Let $L_{μ} (G) = A (G) - μ D (G)$ be the generalized $μ$ -adjacency matrix of a finite graph $G$ . Fan, Xing, Zhang, and Wang constructed pairs of non-degree-similar trees for which the Smith…

math.CO2026

Generalized spectral Turán problems for disjoint cliques

Yi Xu, Yi-Zheng Fan

The generalized Turán number $ex (n, H, F)$ denotes the maximum number of copies of $H$ in an $n$ -vertex $F$ -free graph. Let $k K_{r + 1}$ be the disjoint union of $k$ copies of…

math.CO2026

Signless Laplacian spectral radius of simplicial complexes without $r$ -dimensional wheels

Huan-Zhi Zhang, Yi-Zheng Fan

An $r$ -dimensional wheel is defined as the join of an $(r - 2)$ -simplex and a cycle. In this paper, we study the maximum signless Laplacian spectral radius of $n$ -vertex $r$ -dimensio…

math.CO2026

Maximizing the signless Laplacian spectral radius of simplicial 2-complexes with a prescribed second Betti number

Chuan-Ming She, Yi-Zheng Fan, Yi-Min Song

We study how a prescribed second Betti number constrains the largest eigenvalue of the signless Laplacian on edges of a pure two-dimensional simplicial complex. For each fixed posi…

math.CO2025

Signless Laplacian spectral radius of simplicial complexes without holes

Yi-Zheng Fan, Chuan-Ming She, Huan-Zhi Zhang

We study a spectral analog of the Turán problem for simplicial complexes. Specifically, we consider the extremal problem of maximizing the signless Laplacian spectral radius among…

math.CO2024★ 1 cited

The largest normalized Laplacian eigenvalue and incidence balancedness of simplicial complexes

Yi-min Song, Hui-Feng Wu, Yi-Zheng Fan

Let $K$ be a simplicial complex, and let $Δ_{i}^{u p} (K)$ be the $i$ -th up normalized Laplacian of $K$ . Horak and Jost showed that the largest eigenvalue of $Δ_{i}^{u p} (K)$ is at most $…

math.CO2024★ 2 cited

Spectral bipartite Turan problems on linear hypergraphs

Chuan-Ming She, Yi-Zheng Fan, Liying Kang

Let $F$ be a graph, and let $B_{r} (F)$ be the class of $r$ -uniform Berge- $F$ hypergraphs. In this paper, we establish a relationship between the spectral radius of the adja…

math.CO2023

Hypergraph coverings and Ramanujan Hypergraphs

Yi-Min Song, Yi-Zheng Fan, Zhengke Miao

In this paper we investigate Ramanujan hypergraphs by using hypergraph coverings. We first show that the spectrum of a $k$ -fold covering $H ˉ$ of a connected hypergraph $H$ con…

math.CO2022★ 4 cited

Linear spectral Turan problems for expansions of graphs with given chromatic number

Chuan-Ming She, Yi-Zheng Fan, Liying Kang +1

An $r$ -uniform hypergraph is linear if every two edges intersect in at most one vertex. The $r$ -expansion $F^{r}$ of a graph $F$ is the $r$ -uniform hypergraph obtained from $F$ by…

Tensor Spectral Stability for Uniform Hypergraphs with Bounded Matching Number

Degree Majorization and Laplacian Eigenvalue Sums for Simplicial Complexes

Signless Laplacian Spectral Radius and Link Homology of Simplicial Complexes

Upper Bounds for the Largest Laplacian Eigenvalue of Simplicial Complexes

Orthogonal degree-similarity of edge-deleted strongly regular graphs

Smith normal forms for coalescences at cospectral vertices

Generalized spectral Turán problems for disjoint cliques

Signless Laplacian spectral radius of simplicial complexes without r-dimensional wheels

Maximizing the signless Laplacian spectral radius of simplicial 2-complexes with a prescribed second Betti number

Signless Laplacian spectral radius of simplicial complexes without holes

The largest normalized Laplacian eigenvalue and incidence balancedness of simplicial complexes

Spectral bipartite Turan problems on linear hypergraphs

Hypergraph coverings and Ramanujan Hypergraphs

Linear spectral Turan problems for expansions of graphs with given chromatic number

Signless Laplacian spectral radius of simplicial complexes without $r$ -dimensional wheels