4 papers
Degenerations to filiform Lie algebras of dimension 9
Joan Felipe Herrera-Granada, Oscar Marquez, Sonia Vera
For most complex 9-dimensional filiform Lie algebra we find another non isomorphic Lie algebra that degenerates to it. Since this is already known for nilpotent Lie algebras of ran…
An explicit formula for the distance characteristic polynomial of threshold graphs
Joao Lazzarin, Oscar F. Marquez, Fernando C. Tura
A threshold graph G on n vertices is defined by binary sequence of length n. In this paper we present an explicit formula for computing the distance characteristic polynomial of a…
No Threshold graphs are cospectral
J. Lazzarin, O. F. Márquez, F. Tura
A threshold graph G on n vertices is defined by binary sequence of length n. In this paper we present an explicit formula for computing the characteristic polynomial of a threshold…
Branching laws, some results and new examples
Oscar Marquez, Sebastian Simondi, Jorge A. Vargas
For a connected, noncompact matrix simple Lie group so that a maximal compact subgroup has three dimensional simple ideal, in this note we analyze the admissibility of the…