Dirac’s Theorem on Simplicial Matroids

نویسندگان

  • Raul Cordovil
  • Manoel Lemos
  • Cláudia Linhares Sales
چکیده

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 higherdimensional 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.

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تاریخ انتشار 2006