## Algebraic & Geometric Topology

### Algebraic degrees of stretch factors in mapping class groups

Hyunshik Shin

#### Abstract

We explicitly construct pseudo-Anosov maps on the closed surface of genus $g$ with orientable foliations whose stretch factor $λ$ is a Salem number with algebraic degree $2g$. Using this result, we show that there is a pseudo-Anosov map whose stretch factor has algebraic degree $d$, for each positive even integer $d$ such that  $d ≤ g$.

#### Article information

Source
Algebr. Geom. Topol., Volume 16, Number 3 (2016), 1567-1584.

Dates
Revised: 16 September 2015
Accepted: 21 September 2015
First available in Project Euclid: 28 November 2017

https://projecteuclid.org/euclid.agt/1511895856

Digital Object Identifier
doi:10.2140/agt.2016.16.1567

Mathematical Reviews number (MathSciNet)
MR3523049

Zentralblatt MATH identifier
1356.57017

#### Citation

Shin, Hyunshik. Algebraic degrees of stretch factors in mapping class groups. Algebr. Geom. Topol. 16 (2016), no. 3, 1567--1584. doi:10.2140/agt.2016.16.1567. https://projecteuclid.org/euclid.agt/1511895856

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