English

Badly approximable points for diagonal approximation in solenoids

Number Theory 2020-11-12 v2

Abstract

In this paper we investigate the problem of how well points in finite dimensional p-adic solenoids can be approximated by rationals. The setting we work in was previously studied by Palmer, who proved analogues of Dirichlet's theorem and the Duffin-Schaeffer theorem. We prove a complementary result, showing that the set of badly approximable points has maximum Hausdorff dimension. Our proof is a simple application of the elegant machinery of Schmidt's game.

Keywords

Cite

@article{arxiv.2004.12153,
  title  = {Badly approximable points for diagonal approximation in solenoids},
  author = {Huayang Chen and Alan Haynes},
  journal= {arXiv preprint arXiv:2004.12153},
  year   = {2020}
}

Comments

New version: Clarified some points in proofs. Added more explanation about how to derive the dimension result from the winning property in the setting of p-adic solenoids (Section 2)

R2 v1 2026-06-23T15:05:40.606Z