Borel circle squaring

• 成果类型: Article
• 署名作者: Marks, Andrew S.; Unger, Spencer T.
• 刊物名称: ANNALS OF MATHEMATICS
• ISSN/ISSBN: 0003-486X
• DOI: 10.4007/annals.2017.186.2.4
• 发表日期: 2017
• 页码: 581-605
• 关键词: sets; discrepancy; BOUNDARY; convex

摘要

We give a completely constructive solution to Tarski's circle squaring problem. More generally, we prove a Borel version of an equidecomposition theorem due to Laczkovich. If k >= 1 and A, B subset of R-k are bounded Borel sets with the same positive Lebesgue measure whose boundaries have upper Minkowski dimension less than k, then A and B are equidecomposable by translations using Borel pieces. This answers a question of Wagon. Our proof uses ideas from the study of flows in graphs, and a recent result of Gao, Jackson, Krohne, and Seward on special types of witnesses to the hyperfiniteness of free Borel actions of Z(d).