A proof of Bjorner's totally nonnegative conjecture
arXiv:math/0612332
Abstract
The McMullen Correspondence gives a linear dependence between M-sequences of length |d/2|+1 and f-vectors of simplical d-polytopes. Denote the transfer matrix between g and f by M_d. Recently, Bjorner proved that any 2x2-minor of M_d is nonnegative and conjectured that the same would be true for arbitrary minors. In this paper we answer the question in the affirmative.