{ "id": "2001.02551", "version": "v1", "published": "2020-01-08T14:46:34.000Z", "updated": "2020-01-08T14:46:34.000Z", "title": "Intersection between pencils of tubes, discretized sum-product, and radial projections", "authors": [ "Bochen Liu", "Chun-Yen Shen" ], "categories": [ "math.CA", "math.CO", "math.MG" ], "abstract": "In this paper we prove the following results in the plane. They are related to each other, while each of them has its own interest. First we obtain an $\\epsilon_0$-increment on intersection between pencils of $\\delta$-tubes, under non-concentration conditions. In fact we show it is equivalent to the discretized sum-product problem, thus the $\\epsilon_0$ follows from Bourgain's celebrated result. Then we prove a couple of new results on radial projections. We also discussion about the dependence of $\\epsilon_0$ and make a new conjecture. A tube condition on Frostman measures, after careful refinement, is also given.", "revisions": [ { "version": "v1", "updated": "2020-01-08T14:46:34.000Z" } ], "analyses": { "keywords": [ "radial projections", "intersection", "tube condition", "frostman measures", "bourgains celebrated result" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }