{ "id": "1804.01595", "version": "v2", "published": "2018-04-04T20:05:28.000Z", "updated": "2018-06-22T10:32:27.000Z", "title": "Matching fields and lattice points of simplices", "authors": [ "Georg Loho", "Ben Smith" ], "comment": "33 pages, 18 figures", "categories": [ "math.CO" ], "abstract": "We show that the Chow covectors of a linkage matching field define a bijection of lattice points and we demonstrate how one can recover the linkage matching field from this bijection. This resolves two open questions from Sturmfels & Zelevinsky (1993) on linkage matching fields. For this, we give an explicit construction that associates a bipartite incidence graph of an ordered partition of a common set to all lattice points in a dilated simplex. Given a triangulation of a product of two simplices encoded by a set of bipartite trees, we similarly prove that the bijection from left to right degree vectors of the trees is enough to recover the triangulation. As additional results, we show a cryptomorphic description of linkage matching fields and characterise the flip graph of a linkage matching field in terms of its prodsimplicial flag complex. Finally, we relate our findings to transversal matroids through the tropical Stiefel map.", "revisions": [ { "version": "v2", "updated": "2018-06-22T10:32:27.000Z" } ], "analyses": { "subjects": [ "05E45", "52B20", "52B40", "14T05" ], "keywords": [ "lattice points", "prodsimplicial flag complex", "right degree vectors", "bipartite incidence graph", "linkage matching field define" ], "note": { "typesetting": "TeX", "pages": 33, "language": "en", "license": "arXiv", "status": "editable" } } }