English

Answer to a question of Kolmogorov

Classical Analysis and ODEs 2015-04-21 v2

Abstract

More than 80 years ago Kolmogorov asked the following question. Let ER2E\subseteq \mathbb{R}^{2} be a measurable set with λ2(E)<\lambda^{2}(E)<\infty, where λ2\lambda^2 denotes the two-dimensional Lebesgue measure. Does there exist for every ε>0\varepsilon>0 a contraction f ⁣:ER2f\colon E\to \mathbb{R}^{2} such that λ2(f(E))λ2(E)ε\lambda^{2}(f(E))\geq \lambda^{2}(E)-\varepsilon and f(E)f(E) is a polygon? We answer this question in the negative by constructing a bounded, simply connected open counterexample. Our construction can easily be modified to yield the analogous result in higher dimensions.

Keywords

Cite

@article{arxiv.1210.5758,
  title  = {Answer to a question of Kolmogorov},
  author = {Richárd Balka and Márton Elekes and András Máthé},
  journal= {arXiv preprint arXiv:1210.5758},
  year   = {2015}
}

Comments

5 pages