Dirac's theorem on simplicial matroids

Cordovil, Raul; Lemos, Manoel; Sales, Claudia Linhares

Dirac's theorem on simplicial matroids

Authors

Cordovil, Raul

Lemos, Manoel

Sales, Claudia Linhares

Description

We introduce the notion of k-hyperclique complexes, i.e., the largest simplicial complexes on the set [n] with a fixed k-skeleton. These simplicial complexes are a higher-dimensional analogue of clique (or flag) complexes (case k=2) and they are a rich new class of simplicial complexes. We show that Dirac's theorem on chordal graphs has a higher-dimensional analogue in which graphs and clique complexes get replaced, respectively, by simplicial matroids and k-hyperclique complexes. We prove also a higher-dimensional analogue of Stanley's reformulation of Dirac's theorem on chordal graphs.
11 pages; Annals of Combinatorics, to appear