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arXiv · 2110.13411

Generalized torsions in once punctured torus bundles

Nozomu Sekino
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Abstract

A generalized torsion in a group, an non-trivial element such that some products of its conjugates is the identity. This is an obstruction for a group being bi-orderable. Though it is known that there is a non bi-orderable group without generalized torsions, it is conjectured that 3-manifold groups without generalized torsions are bi-orderable. In this paper, we find generalized torsions in the fundamental groups of once punctured torus bundles which are not bi-orderable. Our result contains a generalized torsion in a tunnel number two hyperbolic once punctured torus bundle.

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Nozomu Sekino. 2021-10-26. Generalized torsions in once punctured torus bundles. https://arxiv.org/abs/2110.13411

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