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arXiv · 2608.24860

The tangent bundle of a generalized Kummer fourfold is obstructed

Alessio Bottini
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Abstract

For a hyper-K\"ahler fourfold $X$ of generalized Kummer type, we construct an infinitesimal deformation of the tangent bundle $T_X$ with non-zero Yoneda square. This is the first example of a stable hyperholomorphic bundle with obstructed deformations.

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Alessio Bottini. 2026-08-25. The tangent bundle of a generalized Kummer fourfold is obstructed. https://arxiv.org/abs/2608.24860

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