English
Related papers

Related papers: On the signless Laplacian spectrum of k-uniform hy…

200 papers

The properties of a hypergraph explored through the spectrum of its unified matrix was made by the authors in [26]. In this paper, we introduce three different hypergraph matrices: unified Laplacian matrix, unified signless Laplacian…

Combinatorics · Mathematics 2024-11-14 R. Vishnupriya , R. Rajkumar

The $\alpha$-Hermitian adjacency matrix $H_\alpha$ of a mixed graph $X$ has been recently introduced. It is a generalization of the adjacency matrix of unoriented graphs. In this paper, we consider a special case of the complex number…

Combinatorics · Mathematics 2022-05-26 Omar Alomari , Mohammad Abudayah , Manal Ghanem

In this paper we define signless Laplacian matrix of a hypergraph and obtain structural properties from its eigenvalues. We generalize several known results for graphs, relating the spectrum of this matrix with structural parameters of the…

Spectral Theory · Mathematics 2024-08-12 Kauê Cardoso , Vilmar Trevisan

We give some graph theoretical formulas for the trace $Tr_k(\mathbb {T})$ of a tensor $\mathbb {T}$ which do not involve the differential operators and auxiliary matrix. As applications of these trace formulas in the study of the spectra of…

Spectral Theory · Mathematics 2013-07-23 Jia-Yu Shao , Liqun Qi , Shenglong Hu

Let $\mathcal{H}$ be a uniform hypergraph. Let $\mathcal{A(H)}$ and $\mathcal{Q(H)}$ be the adjacency tensor and the signless Laplacian tensor of $\mathcal{H}$, respectively. In this note we prove several bounds for the spectral radius of…

Combinatorics · Mathematics 2015-02-24 Xiying Yuan , Man Zhang , Mei Lu

The spectral theory of the normalized Laplacian for chemical hypergraphs is further investigated. The signless normalized Laplacian is introduced and it is shown that its spectrum for classical hypergraphs coincides with the spectrum of the…

Combinatorics · Mathematics 2022-11-09 Eleonora Andreotti , Raffaella Mulas

We introduce a hypergraph matrix, named the unified matrix, and use it to represent the hypergraph as a graph. We show that the unified matrix of a hypergraph is identical to the adjacency matrix of the associated graph. This enables us to…

Combinatorics · Mathematics 2024-11-12 R. Vishnupriya , R. Rajkumar

In this paper, we present several upper bounds for the adjacency and signless Laplacian spectral radii of uniform hypergraphs in terms of degree sequences.

Combinatorics · Mathematics 2017-02-22 Dongmei Chen , Zhibing Chen , Xiao-Dong Zhang

In this paper, we investigate spectral properties of the adjacency tensor, Laplacian tensor and signless Laplacian tensor of general hypergraphs (including uniform and non-uniform hypergraphs). We obtain some bounds for the spectral radius…

Combinatorics · Mathematics 2016-05-20 Changjiang Bu , Jiang Zhou , Lizhu Sun

Let $\mathcal{A}(H)$ and $\mathcal{Q}(H)$ be the adjacency tensor and signless Laplacian tensor of an $r$-uniform hypergraph $H$. Denote by $\rho(H)$ and $\rho(\mathcal{Q}(H))$ the spectral radii of $\mathcal{A}(H)$ and $\mathcal{Q}(H)$,…

Spectral Theory · Mathematics 2016-11-23 Lele Liu , Liying Kang , Erfang Shan

For a $k$-uniform hypergraph $H$, we obtain some trace formulas for the Laplacian tensor of $H$, which imply that $\sum_{i=1}^nd_i^s$ ($s=1,\ldots,k$) is determined by the Laplacian spectrum of $H$, where $d_1,\ldots,d_n$ is the degree…

Combinatorics · Mathematics 2014-07-22 Jiang Zhou , Lizhu Sun , Wenzhe Wang , Changjiang Bu

In this paper, we introduce the Laplacian and the signless Laplacian for the eccentricity matrix of a connected graph, referred to as the eccentricity Laplacian and the eccentricity signless Laplacian, respectively. We establish the…

Combinatorics · Mathematics 2026-05-15 Keshav Saini , Anubha Jindal , K. Palpandi

The concept of the integrated adjacency matrix for mixed graphs was first introduced in [9], where its spectral properties were analyzed in relation to the structural characteristics of the mixed graph. Building upon this foundation, this…

Combinatorics · Mathematics 2025-07-08 G. Kalaivani , R. Rajkumar

A $k$-uniform hypergraph $G=(V,E)$ is called odd-bipartite ([5]), if $k$ is even and there exists some proper subset $V_1$ of $V$ such that each edge of $G$ contains odd number of vertices in $V_1$. Odd-bipartite hypergraphs are…

Combinatorics · Mathematics 2014-03-20 Jia-Yu Shao , Hai-Ying Shan , Bao-feng Wu

In this paper, we give the spectrum of a matrix by using the quotient matrix, then we apply this result to various matrices associated to a graph and a digraph, including adjacency matrix, (signless) Laplacian matrix, distance matrix,…

Combinatorics · Mathematics 2016-12-05 Lihua You , Man Yang , JInxi Li , Liyong Ren

In this paper, we study the analytic connectivity of a $k$-uniform hypergraph $H$, denoted by $\alpha(H)$. In addition to computing the analytic connectivity of a complete $k$-graph, we present several bounds on analytic connectivity that…

Combinatorics · Mathematics 2015-07-13 An Chang , Joshua Cooper , Wei Li

In this paper, we show that the largest Laplacian H-eigenvalue of a $k$-uniform nontrivial hypergraph is strictly larger than the maximum degree when $k$ is even. A tight lower bound for this eigenvalue is given. For a connected…

Spectral Theory · Mathematics 2013-05-14 Shenglong Hu , Liqun Qi , Jinshan Xie

Let $\mathbb{Q}_{k,n}$ be the set of the connected $k$-uniform weighted hypergraphs with $n$ vertices, where $k,n\geq 3$. For a hypergraph $G\in \mathbb{Q}_{k,n}$, let $\mathcal{A}(G)$, $\mathcal{L} (G)$ and $\mathcal{Q} (G)$ be its…

Combinatorics · Mathematics 2022-03-01 Rui Sun , Wen-Huan Wang

We present enumeration results on the number of connected graphs up to 10 vertices for which there is at least one other graph with the same spectrum (a cospectral mate), or at least one other graph with the same Smith normal form…

Combinatorics · Mathematics 2020-08-14 Aida Abiad , Carlos A. Alfaro

This paper investigates spectral properties of the deformed Laplacian matrix, which merges the Laplacian and signless Laplacian matrices of a graph through a one-parameter family of matrices. We present general results on the eigenvalues of…

Combinatorics · Mathematics 2025-12-04 Roberto C. Díaz , Elismar R. Oliveira , Vilmar Trevisan
‹ Prev 1 2 3 10 Next ›