4 citations · 6 across the 6 of their papers we have counts for
10 papers
Christophersen's problem for monomial algebras
Roberto Díaz, Alvaro Liendo
Christophersen's problem predicts that the connected component of the automorphism group of a finite-dimensional local algebra of dimension over an algebraically closed…
The structure of automorphism groups of zero-dimensional monomial algebras
Roberto Díaz, Giancarlo Lucchini Arteche, Gonzalo Manzano-Flores
Let be a zero-dimensional monomial algebra over an algebraically closed field of characteristic zero, that is, a finite-dimensional quotient of a polynomial ring by a monomial…
Characterization of Stanley-Reisner varieties by their automorphism group
Roberto Díaz, José Alejandro Samper
We study the automorphism ind-group of a Stanley-Reisner variety through a combinatorial toolkit on the underlying complex: a facet closure operator, its Demazure roots, and…
Spectral properties of the deformed Laplacian matrix of trees and H-join graphs
Roberto C. Díaz, Elismar R. Oliveira, Vilmar Trevisan
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 o…
Finite-dimensional monomial algebras are determined by their automorphism group
Roberto Díaz, Giancarlo Lucchini Arteche
A monomial algebra is the quotient of a polynomial algebra by an ideal generated by monomials. We prove that finite-dimensional monomial algebras are characterized by their automor…
The Automorphism groups of zero-dimensional monomial algebras
Roberto Díaz, Alvaro Liendo, Gonzalo Manzano-Flores +1
A monomial algebra B is defined as a quotient of a polynomial ring by a monomial ideal, which is an ideal generated by a finite set of monomials. In this paper, we determine the au…
On the characterization of affine toric varieties by their automorphism group
Roberto Díaz, Alvaro Liendo, Andriy Regeta
In this paper we show that a normal affine toric variety X different from the algebraic torus is uniquely determined by its automorphism group in the category of affine irreducible…
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…
Averaging functions on triangular fuzzy numbers
Roberto Díaz, Aldryn Aparcana, Diego Soto +5
Admissible orders on fuzzy numbers are total orders which refine a basic and well-known partial order on fuzzy numbers. In this work, we define an admissible order on triangular fu…
On the automorphism group of non-necessarily normal affine toric varieties
Roberto Díaz, Alvaro Liendo
Our main result is the following: let X be a normal affine toric surface without torus factor. Then there exists a non-normal affine toric surface X' with automorphism group isomor…