5 papers
Singularly cospectral circulant graphs
Cristian M. Conde, Ezequiel Dratman, Luciano N. Grippo +1
Two graphs having the same spectrum are said to be cospectral. Two graphs such that the absolute values of their nonzero eigenvalues coincide are singularly cospectral graphs. Cosp…
On the spectral radius of unbalanced signed bipartite graphs
Cristian M. Conde, Ezequiel Dratman, Luciano N. Grippo
A signed graph is one that features two types of edges: positive and negative. Balanced signed graphs are those in which all cycles contain an even number of positive edges. In the…
On several new results related to Richard's inequality
Cristian Conde, Niçusor Minculete
The main study of this article is the characterization of Richard's inequality, because it is closely related to Buzano's inequality. Finally, we present a newapproach for Richard'…
On a binary operation for positive operators
Shigeru Furuichi, Hamid Reza Moradi, Cristian Conde +1
M. Lin defined a binary operation for two positive semi-definite matrices in studying certain determinantal inequalities that arise from diffusion tensor imaging. This operation en…
A convex-block approach for numerical radius inequalities
Mohammad Sababheh, Cristian Conde, Hamid Reza Moradi
This article implements a simple convex approach and block techniques to obtain several new refined versions of numerical radius inequalities for Hilbert space operators. This incl…