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arXiv · 2601.18701

Hyperkähler bases for six rational bordism theories

Jonathan Buchanan·Arun Debray·Cameron Krulewski·Stephen McKean
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Abstract

We use tori and Hilbert schemes of K3 surfaces to construct explicit bases for the real, complex, and quaternionic versions of rational symplectic and rational Spin bordism. The key input to our work is a theorem of Oberdieck, Song, and Voisin on the Milnor genus of Hilbert schemes of K3s.

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Jonathan Buchanan, Arun Debray, Cameron Krulewski, Stephen McKean. 2026-01-26. Hyperkähler bases for six rational bordism theories. https://arxiv.org/abs/2601.18701

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