1 citations · 2 across the 5 of their papers we have counts for
8 papers
New results about the Inverse Eigenvalue Problem of a Graph
Roberto C. Díaz, Ana I. Julio
All graphs considered are simple and undirected. The Inverse Eigenvalue Problem of a Graph (IEP-G) aims to find all possible spectra for matrices whose entry, for $i\ne…
Indices of diagonalizable and universal realizability of spectra
Charles R. Johnson, Ana I. Julio, Ricardo L. Soto
A list of complex numbers (repeats allowed) is said to be \textit{realizable} if it is the spectrum of an entrywise nonnegative matrix . is \text…
Perturbing eigenvalues of nonnegative centrosymmetric matrices
Roberto C. Díaz, Ana I. Julio, Yankis R. Linares
An matrix is said to be {\it centrosymmetric} if it satisfies the relation , where is the counteridentity matrix. Centrosymmetric matrices ha…
The role of certain Brauer and Rado results in the nonnegative inverse spectral problems
Ana I. Julio, Ricardo L. Soto
We say that a list of complex numbers is realizable, if it is the spectrum of a nonnegative matrix (the realizing matrix). We say that is unive…
Centrosymmetric nonnegative realization of spectra
Ana I. Julio, Oscar Rojo, Ricardo L. Soto
A list of complex numbers is said to be realizable if it is the spectrum of an entrywise nonnegative matrix. In this paper we intent to characteri…
On universal realizability of spectra
Ana I. Julio, Carlos Marijuán, Miriam Pisonero +1
A list of complex numbers is said to be realizable if it is the spectrum of an entrywise nonnegative matrix. The list is said to be universall…
On Fillmore's theorem extended by Borobia
Ana I. Julio, Ricardo L. Soto
Fillmore Theorem says that if A is an nxn complex non-scalar matrix and γ_1,...,γ_{n} are complex numbers with γ_1+...+γ_{n}=trA, then there exists a matrix B similar to A with dia…
New bounds on the distance Laplacian and distance signless Laplacian spectral radii
Roberto C. Díaz, Ana I. Julio, Oscar Rojo
Let G be a simple undirected connected graph. In this paper, new upper bounds on the distance Laplacian spectral radius of G are obtained. Moreover, new lower and upper bounds for…