An elegant and general way to apply graph partitioning
algorithms to hypergraphs would be to model hypergraphs
by graphs and apply the graph algorithms to these
models. Of course such models have to simulate the
given hypergraphs with respect to their cut properties.
An edge-weighted graph (V,E) is a cut-model for an
edge-weighted hypergraph (V,H) if the weight of the
edges cut by any bipartition of V in the graph is the
same as the weight of the hyperedges cut by the same
bipartition in the hypergraph. We show that there is no
cut-model in general. Next we examine whether the
addition of dummy vertices helps: An edge-weighted
graph (Vcup D,E) is a mincut-model for an
edge-weighted hypergraph (V,H) if the weight of the
hyperedges cut by a bipartition of the hypergraphs
vertices is the same as the weight of a minimum cut
separating the two parts in the graph. We construct
such models using positive and negative weights. On
the other hand, we show that there is no mincut-model
in general if only positive weights are allowed.