{ "id": "2103.13774", "version": "v1", "published": "2021-03-25T11:57:36.000Z", "updated": "2021-03-25T11:57:36.000Z", "title": "Sharp growth conditions for boundedness of maximal function in generalized Orlicz spaces", "authors": [ "Petteri Harjulehto", "Arttu Karppinen" ], "categories": [ "math.FA" ], "abstract": "We study sharp growth conditions for the boundedness of the Hardy-Littlewood maximal function in the generalized Orlicz spaces. We assume that the generalized Orlicz function $\\phi(x, t)$ satisfies the standard continuity properties (A0), (A1) and (A2). We show that if the Hardy-Littlewood maximal function is bounded from the generalized Orlicz space to itself then $\\phi(x,t)/ t^p$ is almost increasing for large $t$ for some $p>1$. Moreover we show that the Hardy-Littlewood maximal function is bounded from the generalized Orlicz space $L^\\phi(\\mathbb{R}^n)$ to itself if and only if $\\phi$ is weakly equivalent to a generalized Orlicz function $\\psi$ satisfying (A0), (A1) and (A2) for which $\\psi(x,t)/ t^p$ is almost increasing for all $t>0$ and some $p>1$.", "revisions": [ { "version": "v1", "updated": "2021-03-25T11:57:36.000Z" } ], "analyses": { "subjects": [ "46E30" ], "keywords": [ "generalized orlicz space", "hardy-littlewood maximal function", "generalized orlicz function", "boundedness", "study sharp growth conditions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }