{ "id": "2012.11458", "version": "v1", "published": "2020-12-21T16:23:33.000Z", "updated": "2020-12-21T16:23:33.000Z", "title": "Decoupling for fractal subsets of the parabola", "authors": [ "Alan Chang", "Jaume de Dios Pont", "Rachel Greenfeld", "Asgar Jamneshan", "Zane Kun Li", "José Madrid" ], "comment": "28 pages", "categories": [ "math.CA", "math.NT" ], "abstract": "We consider decoupling for a fractal subset of the parabola. We reduce studying $l^{2}L^{p}$ decoupling for a fractal subset on the parabola $\\{(t, t^2) : 0 \\leq t \\leq 1\\}$ to studying $l^{2}L^{p/3}$ decoupling for the projection of this subset to the interval $[0, 1]$. This generalizes the decoupling theorem of Bourgain-Demeter in the case of the parabola. Due to the sparsity and fractal like structure, this allows us to improve upon Bourgain-Demeter's decoupling theorem for the parabola. In the case when $p/3$ is an even integer we derive theoretical and computational tools to explicitly compute the associated decoupling constant for this projection to $[0, 1]$. Our ideas are inspired by the recent work on ellipsephic sets by Biggs using nested efficient congruencing.", "revisions": [ { "version": "v1", "updated": "2020-12-21T16:23:33.000Z" } ], "analyses": { "keywords": [ "fractal subset", "projection", "computational tools", "bourgain-demeters decoupling theorem", "ellipsephic sets" ], "note": { "typesetting": "TeX", "pages": 28, "language": "en", "license": "arXiv", "status": "editable" } } }