Recognising perfect fits

Layne Hall

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arXiv · 2501.00232

Recognising perfect fits

Layne Hall

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Abstract

A pseudo-Anosov flow is said to have perfect fits if there are stable and unstable leaves that are asymptotic in the universal cover. We give an algorithm to decide, given a box decomposition of a pseudo-Anosov flow, if the flow has perfect fits. As a corollary, we obtain an algorithm to decide whether two flows without perfect fits are orbit equivalent.

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Layne Hall. 2025-11-30. Recognising perfect fits. https://arxiv.org/abs/2501.00232

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