## Functiones et Approximatio Commentarii Mathematici

### A Dirichlet approximation theorem for group actions

#### Abstract

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.

#### Article information

Source
Funct. Approx. Comment. Math., Volume 60, Number 2 (2019), 263-275.

Dates
First available in Project Euclid: 26 June 2018

https://projecteuclid.org/euclid.facm/1529978437

Digital Object Identifier
doi:10.7169/facm/1755

Mathematical Reviews number (MathSciNet)
MR3964265

Zentralblatt MATH identifier
07068536

#### Citation

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

#### References

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