{ "id": "1006.5928", "version": "v1", "published": "2010-06-30T17:18:14.000Z", "updated": "2010-06-30T17:18:14.000Z", "title": "The flag polynomial of the Minkowski sum of simplices", "authors": [ "Geir Agnarsson" ], "comment": "23 pages, 1 figure", "categories": [ "math.CO" ], "abstract": "For a polytope we define the {\\em flag polynomial}, a polynomial in commuting variables related to the well-known flag vector and describe how to express the the flag polynomial of the Minkowski sum of $k$ standard simplices in a direct and canonical way in terms of the {\\em $k$-th master polytope} $P(k)$ where $k\\in\\nats$. The flag polynomial facilitates many direct computations. To demonstrate this we provide two examples; we first derive a formula for the $f$-polynomial and the maximum number of $d$-dimensional faces of the Minkowski sum of two simplices. We then compute the maximum discrepancy between the number of $(0,d)$-chains of faces of a Minkowski sum of two simplices and the number of such chains of faces of a simple polytope of the same dimension and on the same number of vertices.", "revisions": [ { "version": "v1", "updated": "2010-06-30T17:18:14.000Z" } ], "analyses": { "subjects": [ "05A15", "05A16", "52B05", "52B11" ], "keywords": [ "minkowski sum", "th master polytope", "flag polynomial facilitates", "well-known flag vector", "direct computations" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1006.5928A" } } }