English
Related papers

Related papers: L-Borderenergetic graphs and Normalized Laplacian …

200 papers

Let $H=(V,E)$ be an $r$-uniform hypergraph with the vertex set $V$ and the edge set $E$. For $1\leq s \leq r/2$, we define a weighted graph $G^{(s)}$ on the vertex set ${V\choose s}$ as follows. Every pair of $s$-sets $I$ and $J$ is…

Combinatorics · Mathematics 2011-12-06 Linyuan Lu , Xing Peng

We develop the theory of torsional rigidity -- a quantity routinely considered for Dirichlet Laplacians on bounded planar domains -- for Laplacians on metric graphs with at least one Dirichlet vertex. Using a variational characterization…

Spectral Theory · Mathematics 2022-11-11 Delio Mugnolo , Marvin Plümer

Several new spectral properties of the normalized Laplacian defined for oriented hypergraphs are shown. The eigenvalue $1$ and the case of duplicate vertices are discussed; two Courant nodal domain theorems are established; new quantities…

Combinatorics · Mathematics 2021-03-23 Raffaella Mulas , Dong Zhang

Construction of non-isomorphic cospectral graphs is a nontrivial problem in spectral graph theory specially for large graphs. In this paper, we establish that graph theoretical partial transpose of a graph is a potential tool to create…

Combinatorics · Mathematics 2018-08-13 Supriyo Dutta , Bibhas Adhikari

In this paper, we characterize all connected graphs with exactly three distinct normalized Laplacian eigenvalues of which one is equal to $1$, determine all connected bipartite graphs with at least one vertex of degree $1$ having exactly…

Combinatorics · Mathematics 2017-03-28 Xueyi Huang , Qiongxiang Huang

Graphs with few distinct eigenvalues have been investigated extensively. In this paper, we focus on another relevant topic: characterizing graphs with some eigenvalue of large multiplicity. Specifically, the normalized Laplacian matrix of a…

Combinatorics · Mathematics 2020-01-01 Fenglei Tian , Dein Wong

In the following, we give an explicit construction of a Laplacian on the Minkowski curve, with energy forms that bear the geometric characteristic of the structure. The spectrum of the Laplacian is obtained by means of spectral decimation.

Analysis of PDEs · Mathematics 2018-02-06 Nizare Riane , Claire David

We extend the $L^p$ theory of sparse graph limits, which was introduced in a companion paper, by analyzing different notions of convergence. Under suitable restrictions on node weights, we prove the equivalence of metric convergence,…

Combinatorics · Mathematics 2018-02-06 Christian Borgs , Jennifer T. Chayes , Henry Cohn , Yufei Zhao

For a simple and connected graph, a new graph invariant $s_{\alpha}^{*}(G)$, defined as the sum of powers of the eigenvalues of the normalized Laplacian matrix, has been introduced by Bozkurt and Bozkurt in [7]. Lower and upper bounds have…

Combinatorics · Mathematics 2016-08-31 Gian Paolo Clemente , Alessandra Cornaro

The $k$-token graph $F_k(G)$ of a graph $G$ is the graph whose vertices are the $k$-subsets of vertices from $G$, two of which being adjacent whenever their symmetric difference is a pair of adjacent vertices in $G$. In this article, we…

Combinatorics · Mathematics 2024-03-28 M. A. Reyes , C. Dalfó , M. A. Fiol

In this paper, we extend our earlier proposal of corona product of signed graphs into generalized corona product of signed graphs inspired by the generalized corona product of unsigned graphs. Then we study structural balance and spectral…

Combinatorics · Mathematics 2023-10-13 Amrik Singh , Ravi Srivastava , Bibhas Adhikari , Sandeep Kumar Yadav

Threshold graphs are generated from one node by repeatedly adding a node that links to all existing nodes or adding a node without links. In the weighted threshold graph, we add a new node in step $i$, which is linked to all existing nodes…

Combinatorics · Mathematics 2025-06-23 Yingyue Ke , Willem H. Haemers , Piet Van Mieghem

The power graph \( \mathcal{G}_G \) of a group \( G \) is a graph whose vertex set is \( G \), and two elements \( x, y \in G \) are adjacent if one is an integral power of the other. In this paper, we determine the adjacency, Laplacian,…

Spectral Theory · Mathematics 2025-05-06 Basit Auyoob Mir , Fouzul Atik , Priti Prasanna Mondal

Let $K_n$ be the complete graph with $n$ vertices and $c_1, c_2, ..., c_r$ be $r$ different colors. Suppose we randomly and uniformly color the edges of $K_n$ in $c_1, c_2, ..., c_r$. Then we get a random graph, denoted by…

Combinatorics · Mathematics 2007-11-27 Xueliang Li , Jie Zheng

In this note, we present a structural description of certain connected cographs having $k \geq 2$ main signless Laplacian eigenvalues. This result allows us to characterize the cographs which are quasi-threshold graphs with two main…

Combinatorics · Mathematics 2026-02-17 Átila Jones , Vilmar Trevisan , Cybele T. M. Vinagre

Graph energy is the energy of the matrix representation of the graph, where the energy of a matrix is the sum of singular values of the matrix. Depending on the definition of a matrix, one can contemplate graph energy, Randi\'c energy,…

Social and Information Networks · Computer Science 2019-02-12 Mikołaj Morzy , Tomasz Kajdanowicz

In this paper, we introduce the notion of an energy graph as a simple, directed and vertex labeled graph $G$ such that the arcs $(v_i, v_j) \notin A(G)$ if $i > j$ for all distinct pairs $v_i,v_j$ and at least one vertex $v_k$ exists such…

General Mathematics · Mathematics 2016-10-13 Johan Kok , N. K. Sudev , K. P. Chithra , U. Mary

In this paper, we study the spectral fractional Laplacian with inhomogeneous Dirichlet boundary data. Our contributions are twofold: first we introduce a Dirichlet-to-Neumann map for this operator and analyze an associated inverse problem;…

Analysis of PDEs · Mathematics 2026-04-09 Ravi Shankar Jaiswal , Pu-Zhao Kow , Suman Kumar Sahoo

The energy of a graph is the sum of the absolute values of the eigenvalues of its adjacency matrix. This note is about the energy of regular graphs. It is shown that graphs that are close to regular can be made regular with a negligible…

Combinatorics · Mathematics 2016-05-10 V. Nikiforov

In this article, various aspects of Laplacian spectra of power graphs of finite cyclic, dicyclic and finite $p$-groups are studied. Algebraic connectivity of power graphs of the above groups are considered and determined completely for that…

Combinatorics · Mathematics 2018-11-13 Ramesh Prasad Panda
‹ Prev 1 8 9 10 Next ›