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arXiv · 0909.4517

Small dilatation pseudo-Anosov mapping classes coming from the simplest hyperbolic braid

Eriko Hironaka
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Abstract

In this paper we study the minimum dilatation pseudo-Anosov mapping classes coming from fibrations over the circle of a single 3-manifold, the mapping torus for the "simplest pseudo-Anosov braid". The dilatations that arise include the minimum dilatations for orientable mapping classes for genus g=2,3,4,5,8 as well as Lanneau and Thiffeault's conjectural minima for orientable mapping classes, when g = 2,4 (mod 6). Our examples also show that the minimum dilatation for orientable mapping classes is strictly greater than the minimum dilatation for non-orientable ones when g = 4,6,8.

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Eriko Hironaka. 2010-04-16. Small dilatation pseudo-Anosov mapping classes coming from the simplest hyperbolic braid. https://doi.org/10.2140/agt.2010.10.2041

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