{ "id": "1902.00353", "version": "v1", "published": "2019-02-01T14:26:29.000Z", "updated": "2019-02-01T14:26:29.000Z", "title": "A counterexample to a strong variant of the Polynomial Freiman-Ruzsa conjecture", "authors": [ "James Aaronson" ], "comment": "3 pages", "categories": [ "math.CO" ], "abstract": "Let $p$ be a prime. One formulation of the Polynomial Freiman-Ruzsa conjecture over $\\mathbb{F}_p$ can be stated as follows. If $\\phi : \\mathbb{F}_p^n \\rightarrow \\mathbb{F}_p^N$ is a function such that $\\phi(x+y) - \\phi(x) - \\phi(y)$ takes values in some set $S$, then there is a linear map $\\tilde{\\phi} : \\mathbb{F}_p^n \\rightarrow \\mathbb{F}_p^N$ with the property that $\\phi - \\tilde{\\phi}$ takes at most $|S|^{O(1)}$ values. A strong variant of this conjecture states that, in fact, there is a linear map $\\tilde{\\phi}$ such that $\\phi - \\tilde{\\phi}$ takes values in $tS$ for some constant $t$. In this note, we discuss a counterexample to this conjecture.", "revisions": [ { "version": "v1", "updated": "2019-02-01T14:26:29.000Z" } ], "analyses": { "keywords": [ "polynomial freiman-ruzsa conjecture", "strong variant", "counterexample", "linear map", "conjecture states" ], "note": { "typesetting": "TeX", "pages": 3, "language": "en", "license": "arXiv", "status": "editable" } } }