Exotically knotted 2-spheres and the fundamental groups of their complements

Younes Benyahia

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arXiv · 2406.07093

Exotically knotted 2-spheres and the fundamental groups of their complements

Younes Benyahia

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Abstract

We show that for any finitely presented group $G$, there is a simply connected closed 4-manifold containing an infinite family of topologically isotopic but smoothly inequivalent 2-links whose 2-link group is $G$. We also show that, if $G$ satisfies the necessary topological conditions, these 2-links have nullhomotopic components.

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Younes Benyahia. 2024-06-11. Exotically knotted 2-spheres and the fundamental groups of their complements. https://arxiv.org/abs/2406.07093

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