{ "id": "1809.10100", "version": "v1", "published": "2018-09-26T16:16:32.000Z", "updated": "2018-09-26T16:16:32.000Z", "title": "Electrical networks and frame matroids", "authors": [ "Bob Lutz" ], "comment": "22 pages, 9 figures", "categories": [ "math.CO" ], "abstract": "This paper defines Dirichlet matroids, a class of matroids arising from electrical networks and almost-balanced biased graphs. We prove four main results. First we use properties of the electrical response matrix to show that every Dirichlet matroid has the half-plane property. Second we bound the coefficients of the precoloring polynomial in terms of the chromatic polynomial. Third we prove a simple characterization of 3-connected Dirichlet matroids. And fourth we prove a circular network analog of the duality theorem for planar graphic matroids.", "revisions": [ { "version": "v1", "updated": "2018-09-26T16:16:32.000Z" } ], "analyses": { "subjects": [ "05B35", "05C22", "05C15", "05C40", "34B45" ], "keywords": [ "electrical networks", "frame matroids", "paper defines dirichlet matroids", "circular network analog", "planar graphic matroids" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }