English

Some constructions for the higher-dimensional three-distance theorem

Number Theory 2018-06-08 v1 Dynamical Systems

Abstract

For a given real number α\alpha, let us place the fractional parts of the points 0,α,2α,0, \alpha, 2 \alpha, ,(N1)α \cdots, (N-1) \alpha on the unit circle. These points partition the unit circle into intervals having at most three lengths, one being the sum of the other two. This is the three distance theorem. We consider a two-dimensional version of the three distance theorem obtained by placing on the unit circle the points nα+mβ n\alpha+ m\beta , for 0n,m<N0 \leq n,m < N. We provide examples of pairs of real numbers (α,β)(\alpha,\beta), with 1,α,β1,\alpha, \beta rationally independent, for which there are finitely many lengths between successive points (and in fact, seven lengths), with (α,β)(\alpha,\beta) not badly approximable, as well as examples for which there are infinitely many lengths.

Keywords

Cite

@article{arxiv.1806.02721,
  title  = {Some constructions for the higher-dimensional three-distance theorem},
  author = {Valérie Berthé and Dong Han Kim},
  journal= {arXiv preprint arXiv:1806.02721},
  year   = {2018}
}

Comments

To appear in Acta Arithmetica

R2 v1 2026-06-23T02:22:34.196Z