Edge connectivity of simplicial polytopes

We show that the graph of a simplicial polytope dimension d≥3 has no nontrivial minimum edge cut with fewer than d(d+1)/2 edges, hence is min{δ,d(d+1)/2}-edge-connected where δ denotes degree. When d=3, this implies every in plane triangulation trivial. d≥4, we construct d-polytope whose cardinality d(d+1)/2, proving aforementioned result best possible.