{ "id": "2305.11587", "version": "v1", "published": "2023-05-19T10:55:50.000Z", "updated": "2023-05-19T10:55:50.000Z", "title": "On the Hausdorff dimension of circular Furstenberg sets", "authors": [ "Katrin Fässler", "Jiayin Liu", "Tuomas Orponen" ], "comment": "73 pages, 5 figures", "categories": [ "math.CA", "math.MG" ], "abstract": "For $0 \\leq s \\leq 1$ and $0 \\leq t \\leq 3$, a set $F \\subset \\mathbb{R}^{2}$ is called a circular $(s,t)$-Furstenberg set if there exists a family of circles $\\mathcal{S}$ of Hausdorff dimension $\\dim_{\\mathrm{H}} \\mathcal{S} \\geq t$ such that $$\\dim_{\\mathrm{H}} (F \\cap S) \\geq s, \\qquad S \\in \\mathcal{S}.$$ We prove that if $0 \\leq t \\leq s \\leq 1$, then every circular $(s,t)$-Furstenberg set $F \\subset \\mathbb{R}^{2}$ has Hausdorff dimension $\\dim_{\\mathrm{H}} F \\geq s + t$. The case $s = 1$ follows from earlier work of Wolff on circular Kakeya sets.", "revisions": [ { "version": "v1", "updated": "2023-05-19T10:55:50.000Z" } ], "analyses": { "subjects": [ "28A80", "28A78" ], "keywords": [ "circular furstenberg sets", "hausdorff dimension", "circular kakeya sets", "earlier work" ], "note": { "typesetting": "TeX", "pages": 73, "language": "en", "license": "arXiv", "status": "editable" } } }