Abstract:

I will define hypergraphs and explain a Hopf structure on them. Using orientations on hypergraphs we provide an explicit bijection between acyclic orientations on them and faces of hypergraphic polytopes. This allows us to obtain a geometric interpretation of the coefficients of the antipode map in this Hopf algebra. This interpretation differs from similar ones for a different Hopf structure on hypergraphs provided recently by Aguiar and Ardila.