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arXiv · 2211.12741

Homotopy Types of Suspended $4$-manifolds

Pengcheng Li
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Abstract

Given a closed, smooth, connected, orientable $4$-manifold $M$, whose integral homology groups can have $2$-torsion, we determine the homotopy decomposition of the double suspension $\Sigma^2M$ as wedge sums of some elementary $\mathbf{A}_3^3$-complexes, which are $2$-connected finite complexes of dimension at most $6$. Furthermore, we utilize the Postnikov square (or equivalently Pontryagin square) to find sufficient conditions for the homotopy decompositions of $\Sigma^2M$ to desuspend to that of $\Sigma M$.

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Pengcheng Li. 2022-11-23. Homotopy Types of Suspended $4$-manifolds. https://arxiv.org/abs/2211.12741

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