Irreducible 4-manifolds can admit exotic diffeomorphisms

David Baraglia; Hokuto Konno

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arXiv · 2412.14398

Irreducible 4-manifolds can admit exotic diffeomorphisms

David Baraglia·Hokuto Konno

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Abstract

We prove that a variety of examples of minimal complex surfaces admit exotic diffeomorphisms, providing the first known instances of exotic diffeomorphisms of irreducible 4-manifolds. We also give sufficient conditions for the boundary Dehn twist on a spin 4-manifold with $S^3$ boundary to be non-trivial in the relative mapping class group. This gives many new examples of non-trivial boundary Dehn twists.

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BibTeX RIS

David Baraglia, Hokuto Konno. 2024-12-18. Irreducible 4-manifolds can admit exotic diffeomorphisms. https://arxiv.org/abs/2412.14398

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