U torsion structure in Heegaard Floer homology

Yuhui Chen; Shunyu Wan

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arXiv · 2610.27646

U torsion structure in Heegaard Floer homology

Yuhui Chen·Shunyu Wan

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Abstract

We construct infinite families of Brieskorn spheres with three singular fibers for which the difference between the largest and the second largest length of U-torsion in their Heegaard Floer homology $HF^-$ increases to infinity as the family parameter increases. In particular, these families give a negative answer to the strong geography restriction on rational homology spheres. As an application, these families give the examples of integer homology spheres that are neither surgery on a knot nor large surgery on links.

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BibTeX RIS

Yuhui Chen, Shunyu Wan. 2026-10-20. U torsion structure in Heegaard Floer homology. https://arxiv.org/abs/2610.27646

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