## Duke Mathematical Journal

### Lyapunov spectrum of ball quotients with applications to commensurability questions

#### Abstract

We determine the Lyapunov spectrum of ball quotients arising from cyclic coverings. The computations are performed by rewriting the sum of Lyapunov exponents as ratios of intersection numbers and by the analysis of the period map near boundary divisors.

As a corollary, we complete the classification of commensurability classes of all presently known nonarithmetic ball quotients.

#### Article information

Source
Duke Math. J., Volume 165, Number 1 (2016), 1-66.

Dates
Revised: 2 July 2014
First available in Project Euclid: 14 October 2015

https://projecteuclid.org/euclid.dmj/1444828413

Digital Object Identifier
doi:10.1215/00127094-3165969

Mathematical Reviews number (MathSciNet)
MR3450741

Zentralblatt MATH identifier
1334.22010

Subjects

#### Citation

Kappes, André; Möller, Martin. Lyapunov spectrum of ball quotients with applications to commensurability questions. Duke Math. J. 165 (2016), no. 1, 1--66. doi:10.1215/00127094-3165969. https://projecteuclid.org/euclid.dmj/1444828413

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