{ "id": "1702.00602", "version": "v1", "published": "2017-02-02T10:06:35.000Z", "updated": "2017-02-02T10:06:35.000Z", "title": "Unions of cubes in $\\mathbb{R}^{n}$, combinatorics in $\\mathbb{Z}^{n}$ and the John-Nirenberg and John-Strömberg inequalities", "authors": [ "Michael Cwikel" ], "comment": "23 pages", "categories": [ "math.FA", "math.MG" ], "abstract": "Suppose that the $d$-dimensional unit cube $Q$ is the union of three disjoint \"simple\" sets $E$, $F$ and $G$ and that the volumes of $E$ and $F$ are both greater than half the volume of $G$. Does this imply that, for some cube $W$ contained in $Q$. the volumes of $E\\cap W$ and $F\\cap W$ both exceed $s$ times the volume of $W$ for some absolute positive constant $s$? Here, by \"simple\" we mean a set which is a union of finitely many dyadic cubes. We prove that an affirmative answer to this question would have deep consequences for the important space $BMO$ of functions of bounded mean oscillation introduced by John and Nirenberg. The notion of a John-Str\\\"omberg pair is closely related to the above question, and the above mentioned result is obtained as a consequence of a general result about these pairs. We also present a number of additional results about these pairs.", "revisions": [ { "version": "v1", "updated": "2017-02-02T10:06:35.000Z" } ], "analyses": { "subjects": [ "30H35", "42B35", "46E35" ], "keywords": [ "john-strömberg inequalities", "combinatorics", "john-nirenberg", "dimensional unit cube", "additional results" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable" } } }