Abstract (EN):
In this paper we consider the cocircuit graph G(M) Of an Oriented matroid M, the 1-skeleton of the cell complex W formed by the span of the cocircuits of M. In general, W is not determined by G(M) However, we show that if the vertex set (resp. edge set) of GM is properly labeled by the hyperplanes (resp. colines) of M, G(M) determines W. Also we prove that, when M is uniform, the cocircuit graph together with all antipodal pairs of vertices being marked determines W. These results can be considered as variations of Blind-Mani's theorem that says the 1-skeleton of a simple convex polytope determines its face lattice.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Nº de páginas:
9