KAIST Discrete Math Seminar

Wiring diagrams are widely used combinatorial objects that are mainly used to describe reduced words of a permutation. In this talk, I will mention a fun property I recently found about those diagrams, and then introduce other results and problems related to this property.

A transversal matroid is a collection of objects that encodes maximal matchings in a bipartite graph. Generalized permutohedra is a class of polytopes obtained by deforming the permutohedron. We introduce a nice bijection that allows one to view transversal matroids as set of lattice points inside a generalized permutohedron. As a corollary, we solve a special case of the 30-year old conjecture by Stanley on matroids and pure O-sequences. The talk will be elementary and purely combinatorial.