{ "id": "1802.04984", "version": "v1", "published": "2018-02-14T08:20:57.000Z", "updated": "2018-02-14T08:20:57.000Z", "title": "On ranks of polynomials", "authors": [ "David Kazhdan", "Tamar Ziegler" ], "categories": [ "math.AG", "math.CO" ], "abstract": "Let $V$ be a vector space over a field $k, P:V\\to k, d\\geq 3$. We show the existence of a function $C(r,d)$ such that $rank (P)\\leq C(r,d)$ for any field $k,char (k)>d$, a finite-dimensional $k$-vector space $V$ and a polynomial $P:V\\to k$ of degree $d$ such that $rank(\\partial P/\\partial t)\\leq r$ for all $t\\in V-0$. Our proof of this theorem is based on the application of results on Gowers norms for finite fields $k$. We don't know a direct proof in the case when $k=\\mathbb C$.", "revisions": [ { "version": "v1", "updated": "2018-02-14T08:20:57.000Z" } ], "analyses": { "keywords": [ "polynomial", "vector space", "gowers norms", "finite fields", "direct proof" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }