{ "id": "1802.02836", "version": "v1", "published": "2018-02-08T12:50:36.000Z", "updated": "2018-02-08T12:50:36.000Z", "title": "Convolutions of sets with bounded VC-dimension are uniformly continuous", "authors": [ "Olof Sisask" ], "comment": "17 pages", "categories": [ "math.CO", "math.CA" ], "abstract": "We introduce a notion of VC-dimension for subsets of groups, defining this for a set $A$ to be the VC-dimension of the family $\\{ A \\cap(xA) : x \\in A\\cdot A^{-1} \\}$. We show that if a finite subset $A$ of an abelian group has bounded VC-dimension, then the convolution $1_A*1_{-A}$ is Bohr uniformly continuous, in a quantitatively strong sense. This generalises and strengthens a version of the stable arithmetic regularity lemma of Terry and Wolf in various ways. In particular, it directly implies that the Polynomial Bogolyubov--Ruzsa Conjecture --- a strong version of the Polynomial Freiman--Ruzsa Conjecture --- holds for sets with bounded VC-dimension. We also prove some results in the non-abelian setting.", "revisions": [ { "version": "v1", "updated": "2018-02-08T12:50:36.000Z" } ], "analyses": { "keywords": [ "bounded vc-dimension", "uniformly continuous", "convolution", "polynomial bogolyubov-ruzsa conjecture", "polynomial freiman-ruzsa conjecture" ], "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable" } } }