Nonsmoothable actions of Z2 * Z2 on spin four-manifolds

Yuya Kato

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arXiv · 1708.08030

Nonsmoothable actions of Z2 * Z2 on spin four-manifolds

Yuya Kato

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Abstract

We construct some nonsmoothable actions of Z2 * Z2 on spin four-manifolds by using an equivariant version of Furuta' s 10/8inequality. The examples satisfy following property: any proper subgroup of Z2 * Z2 is smoothable for some smooth structure.

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Yuya Kato. 2017-08-27. Nonsmoothable actions of Z2 * Z2 on spin four-manifolds. https://arxiv.org/abs/1708.08030

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