Exotic aspherical 4-manifolds

Michael Davis; Kyle Hayden; Jingyin Huang; Daniel Ruberman; Nathan Sunukjian

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arXiv · 2411.19400

Exotic aspherical 4-manifolds

Michael Davis·Kyle Hayden·Jingyin Huang·Daniel Ruberman·Nathan Sunukjian

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Abstract

We construct closed, aspherical, smooth 4-manifolds that are homeomorphic but not diffeomorphic. These provide counterexamples to a smooth analog of the Borel conjecture in dimension four. Our technique is to apply the `reflection group trick' of the first author to pairs of exotic 4-manifolds with boundary constructed by the second author and Piccirillo.

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Michael Davis, Kyle Hayden, Jingyin Huang, Daniel Ruberman, Nathan Sunukjian. 2024-11-28. Exotic aspherical 4-manifolds. https://arxiv.org/abs/2411.19400

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