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arXiv · math/0608517

The Heegaard genus of bundles over S^1

Abstract

This paper explores connections between Heegaard genus, minimal surfaces, and pseudo-Anosov monodromies. Fixing a pseudo-Anosov map phi and an integer n, let M_n be the 3-manifold fibered over S^1 with monodromy phi^n. JH Rubinstein showed that for a large enough n every minimal surface of genus at most h in M_n is homotopic into a fiber; as a consequence Rubinstein concludes that every Heegaard surface of genus at most h for M_n is standard, that is, obtained by tubing together two fibers. We prove this result and also discuss related results of Lackenby and Souto.

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Mark Brittenham, Yo'av Rieck. 2009-03-30. The Heegaard genus of bundles over S^1. https://doi.org/10.2140/gtm.2007.12.17

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