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arXiv · 2307.16454

A cork of the rational surface with the second Betti number 9

Yohei Wakamaki
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Abstract

We provide the first explicit example of a cork of $\mathbf{CP}^2 \# 8\overline{\mathbf{CP}^2}$. This result gives the current smallest second Betti number of a standard simply-connected closed $4$-manifold for which an explicit cork has been found.

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Yohei Wakamaki. 2024-09-27. A cork of the rational surface with the second Betti number 9. https://doi.org/10.1016/j.topol.2024.109002

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