Search engine for discovering works of Art, research articles, and books related to Art and Culture
ShareThis
Javascript must be enabled to continue!

Universal Adjacency Matrices with Two Eigenvalues

View through CrossRef
Consider a graph Ґ on n vertices with adjacency matrix A and degree sequence (d1, . . . , dn). A universal adjacency matrix of Ґ is any matrix in Span {A,D, I, J} with a nonzero coefficient for A, where D = diag (d1, . . . , dn) and I and J are the n × n identity and all-ones matrix, respectively. Thus a universal adjacency matrix is a common generalization of the adjacency, the Laplacian, the signless Laplacian and the Seidel matrix. We investigate graphs for which some universal adjacency matrix has just two eigenvalues. The regular ones are strongly regular, complete or empty, but several other interesting classes occur.
Title: Universal Adjacency Matrices with Two Eigenvalues
Description:
Consider a graph Ґ on n vertices with adjacency matrix A and degree sequence (d1, .
.
.
, dn).
A universal adjacency matrix of Ґ is any matrix in Span {A,D, I, J} with a nonzero coefficient for A, where D = diag (d1, .
.
.
, dn) and I and J are the n × n identity and all-ones matrix, respectively.
Thus a universal adjacency matrix is a common generalization of the adjacency, the Laplacian, the signless Laplacian and the Seidel matrix.
We investigate graphs for which some universal adjacency matrix has just two eigenvalues.
The regular ones are strongly regular, complete or empty, but several other interesting classes occur.

Related Results

Funkcije komunikacijski relevantne šutnje u njemačkome
Funkcije komunikacijski relevantne šutnje u njemačkome
Additionally, this chapter presents research of silence with review of main aspects of papers in the field of conversational analysis, ethnography of communication and metaphor of ...
Methods for detecting “missing” dimensions in genetic covariance matrices
Methods for detecting “missing” dimensions in genetic covariance matrices
Abstract Blows and Hoffmann (2005) and others have suggested that low levels of genetic variation in some dimensions of an additive genetic varia...
On Goethals and Seidel Array
On Goethals and Seidel Array
Objectives: In this article, we aim to find a series of Hadamard matrices by suitable selection of the special class of matrices given in the Goethals and Seidel array and study th...
The second four-electron singlet in the Hubbard impurity model
The second four-electron singlet in the Hubbard impurity model
We consider the energy operator of four-electron systems in the Hubbard impurity model and investigate the structure of the essential spectrum and discrete spectra for the second s...
Investigating the Connection between Atom Connectivity, Connectivity Energy, and the Physico-Chemical Properties of Amino Acids
Investigating the Connection between Atom Connectivity, Connectivity Energy, and the Physico-Chemical Properties of Amino Acids
This research explores the use of molecular graph theory to predict the physical and chemical properties of twenty amino acids. Specifically, it examines how the energy of a graph...
Subespacios hiperinvariantes y característicos : una aproximación geométrica
Subespacios hiperinvariantes y característicos : una aproximación geométrica
The aim of this thesis is to study the hyperinvariant and characteristic subspaces of a matrix, or equivalently, of an endomorphism of a finite dimensional vector space. We restric...
Eigenvalues of normalized Laplacian matrices of fractal trees and dendrimers: Analytical results and applications
Eigenvalues of normalized Laplacian matrices of fractal trees and dendrimers: Analytical results and applications
The eigenvalues of the normalized Laplacian matrix of a network play an important role in its structural and dynamical aspects associated with the network. In this paper, we study ...

Back to Top