{ "id": "2310.00425", "version": "v1", "published": "2023-09-30T16:10:01.000Z", "updated": "2023-09-30T16:10:01.000Z", "title": "A note on bilinear spherical maximal functions", "authors": [ "Ankit Bhojak", "Surjeet Singh Choudhary", "Saurabh Shrivastava", "Kalachand Shuin" ], "comment": "13 pages", "categories": [ "math.CA" ], "abstract": "In this article we address endpoint issues for the bilinear spherical maximal functions. We study necessary conditions for the bilinear maximal function, \\[\\mathcal M (f,g)(x)=\\sup_{t>0}\\left|\\int_{\\mathbb S^{1}}f(x-ty)g(x+ty)\\;d\\sigma(y)\\right|\\] to be bounded from $L^{p_1}(\\mathbb R^2)\\times L^{p_2}(\\mathbb R^2)$ to $L^p(\\mathbb R^2)$ and prove sharp results for a linearizarion of $\\mathcal M$. We also obtain borderline restricted weak type estimates for the well studied operator $$\\mathfrak{M}(f,g)(x):=\\sup_{t>0}\\left|\\int_{\\mathbb S^{1}}f(x-ty_1)g(x-ty_2)\\;d\\sigma(y_1,y_2)\\right|,$$ in dimension one and as a consequence, deduce similar estimates for a multilinear analogue of $\\mathfrak{M}$.", "revisions": [ { "version": "v1", "updated": "2023-09-30T16:10:01.000Z" } ], "analyses": { "subjects": [ "42B15", "42B25" ], "keywords": [ "bilinear spherical maximal functions", "borderline restricted weak type estimates", "bilinear maximal function", "study necessary conditions", "deduce similar estimates" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }