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arXiv · 2402.16167

A note on homotopy and pseudoisotopy of diffeomorphisms of $4$-manifolds

Manuel Krannich·Alexander Kupers
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Abstract

This note serves to record examples of diffeomorphisms of closed smooth $4$-manifolds $X$ that are homotopic but not pseudoisotopic to the identity, and to explain why there are no such examples when $X$ is orientable and its fundamental group is a free group.

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Manuel Krannich, Alexander Kupers. 2024-09-18. A note on homotopy and pseudoisotopy of diffeomorphisms of $4$-manifolds. https://arxiv.org/abs/2402.16167

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