Hostname: page-component-76fb5796d-45l2p Total loading time: 0 Render date: 2024-04-25T09:18:17.619Z Has data issue: false hasContentIssue false

ON SIMULTANEOUSLY BADLY APPROXIMABLE NUMBERS

Published online by Cambridge University Press:  24 March 2003

ANDREW POLLINGTON
Affiliation:
Department of Mathematics, Brigham Young University, Provo, UT 84602, USAandy@math.byu.edu
SANJU VELANI
Affiliation:
Department of Mathematics, Queen Mary, London, Mile End Road, London E1 4NS s.velani@qmw.ac.uk
Get access

Abstract

For any pair $i,j\ge 0$ with $i+j=1$ let ${\mathbf Bad}(i,j)$ denote the set of pairs $(\alpha,\beta)\in {\bb R}^2$ for which $\max\{\|q\alpha\|^{1/i}\|q\beta\|^{1/j}\}>c/q$ for all $q\in {\bb N}$ . Here $c=c(\alpha,\beta)$ is a positive constant. If $i=0$ the set ${\mathbf Bad}(0, 1)$ is identified with ${\bb R}\times {\mathbf Bad}$ where ${\mathbf Bad}$ is the set of badly approximable numbers. That is, ${\mathbf Bad}(0, 1)$ consists of pairs $(\alpha, \beta)$ with $\alpha\in {\bb R}$ and $\beta\in {\mathbf Bad}$ If $j=0$ the roles of $\alpha$ and $\beta$ are reversed. It is proved that the set ${\mathbf Bad}(1,0)\cap {\mathbf Bad} (0,1)\cap {\mathbf Bad}(i,j)$ has Hausdorff dimension 2, that is, full dimension. The method easily generalizes to give analogous statements in higher dimensions.

Type
Notes and Papers
Copyright
The London Mathematical Society, 2002

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)