Functiones et Approximatio Commentarii Mathematici
- Funct. Approx. Comment. Math.
- Volume 60, Number 2 (2019), 263-275.
A Dirichlet approximation theorem for group actions
If $G$ is a compact group acting continuously on a compact metric space $(X, m)$, we prove two results that generalize Dirichlet's classical theorem on Diophantine approximation. If $G$ is a noncommutative compact group of isometries, we obtain a noncommutative form of Dirichlet's theorem. We apply our general result to the special case of the unitary group $U(N)$ acting on the complex unit sphere, and obtain a noncommutative result in this setting.
Funct. Approx. Comment. Math., Volume 60, Number 2 (2019), 263-275.
First available in Project Euclid: 26 June 2018
Permanent link to this document
Digital Object Identifier
Mathematical Reviews number (MathSciNet)
Zentralblatt MATH identifier
Primary: 11J25: Diophantine inequalities [See also 11D75]
Secondary: 37B05: Transformations and group actions with special properties (minimality, distality, proximality, etc.) 22F10: Measurable group actions [See also 22D40, 28Dxx, 37Axx]
Petsche, Clayton; Vaaler, Jeffrey D. A Dirichlet approximation theorem for group actions. Funct. Approx. Comment. Math. 60 (2019), no. 2, 263--275. doi:10.7169/facm/1755. https://projecteuclid.org/euclid.facm/1529978437