{ "id": "1806.01197", "version": "v1", "published": "2018-06-04T16:39:33.000Z", "updated": "2018-06-04T16:39:33.000Z", "title": "Hölder curves and parameterizations in the Analyst's Traveling Salesman theorem", "authors": [ "Matthew Badger", "Lisa Naples", "Vyron Vellis" ], "comment": "70 pages, 4 figures", "categories": [ "math.CA", "math.MG" ], "abstract": "We investigate the geometry of sets in Euclidean and infinite-dimensional Hilbert spaces. We establish sufficient conditions that ensure a set of points is contained in the image of a $(1/s)$-H\\\"older continuous map $f:[0,1]\\rightarrow l^2$, with $s>1$. Our results are motivated by and generalize the \"sufficient half\" of the Analyst's Traveling Salesman Theorem, which characterizes subsets of rectifiable curves in $\\mathbb{R}^N$ or $l^2$ in terms of a quadratic sum of linear approximation numbers called Jones' beta numbers. The original proof of the Analyst's Traveling Salesman Theorem depends on a well-known metric characterization of rectifiable curves from the 1920s, which is not available for higher-dimensional curves such as H\\\"older curves. To overcome this obstacle, we reimagine Jones' non-parametric proof and show how to construct parameterizations of the intermediate approximating curves $f_k([0,1])$. We then find conditions in terms of tube approximations that ensure the approximating curves converge to a H\\\"older curve. As an application, we provide sufficient conditions to guarantee fractional rectifiability of pointwise doubling measures in $\\mathbb{R}^N$.", "revisions": [ { "version": "v1", "updated": "2018-06-04T16:39:33.000Z" } ], "analyses": { "subjects": [ "28A75", "26A16", "28A80", "30L05", "65D10" ], "keywords": [ "analysts traveling salesman theorem", "hölder curves", "parameterizations", "approximating curves", "well-known metric characterization" ], "note": { "typesetting": "TeX", "pages": 70, "language": "en", "license": "arXiv", "status": "editable" } } }