A recipe for exotic 2-links in closed 4-manifolds whose components are topological unknots

Valentina Bais; Younes Benyahia; Oliviero Malech; Rafael Torres

doi:10.2140/pjm.2025.338.35

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arXiv · 2206.09659

A recipe for exotic 2-links in closed 4-manifolds whose components are topological unknots

Valentina Bais·Younes Benyahia·Oliviero Malech·Rafael Torres

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Abstract

We describe a construction procedure of infinite sets of $2$-links in closed simply connected 4-manifolds that are topologically isotopic, smoothly inequivalent and componentwise topologically unknotted. These 2-links are the first examples of such kind in the literature. The examples provided have surface and free groups as their 2-link groups. We also point out an exotic Brunnian behaviour of such families, which highlights the important role of linking in creating exotic phenomena.

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Valentina Bais, Younes Benyahia, Oliviero Malech, Rafael Torres. 2022-06-20. A recipe for exotic 2-links in closed 4-manifolds whose components are topological unknots. https://doi.org/10.2140/pjm.2025.338.35

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