{ "id": "1702.04051", "version": "v1", "published": "2017-02-14T02:42:21.000Z", "updated": "2017-02-14T02:42:21.000Z", "title": "Weak dual equivalence for polynomials", "authors": [ "Sami Assaf" ], "comment": "26 pages, 23 figures", "categories": [ "math.CO" ], "abstract": "We use dual equivalence to give a short, combinatorial proof that Stanley symmetric functions are Schur positive. We introduce weak dual equivalence, and use it to give a short, combinatorial proof that Schubert polynomials are key positive. To demonstrate further the utility of this new tool, we use weak dual equivalence to prove a nonnegative Littlewood--Richardson rule for the key expansion of the product of a key polynomial and a Schur polynomial, and to introduce skew key polynomials that, when skewed by a partition, expand nonnegatively in the key basis.", "revisions": [ { "version": "v1", "updated": "2017-02-14T02:42:21.000Z" } ], "analyses": { "subjects": [ "05E05", "05A15", "05A19", "05E10", "05E18", "14N15" ], "keywords": [ "weak dual equivalence", "combinatorial proof", "stanley symmetric functions", "schur polynomial", "schubert polynomials" ], "note": { "typesetting": "TeX", "pages": 26, "language": "en", "license": "arXiv", "status": "editable" } } }