4.1. Combinatorics [03EH]
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4.1. Combinatorics
It would be interesting to know whether the subdivision of given by the can be realized as the boundary of a -dimensional polytope (as the picture suggests). The dual of the face lattice would be given by the lattice of intervals in the face lattice of (or of ).
In fact, if there was a realization of the combinatorial type of with an identification such that the normal cones of and intersect in their relative interiors, then the Minkowski sum would do the trick. For , Koebe’s Theorem [Thu80] guarantees such a realization.