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arXiv · 2607.05603

Homology fiber bundles of varieties, that are not topological fiber bundles

Maurício Corrêa·János Kollár
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Abstract

We construct flat, projective morphisms that are $\mathbb Z$-homology fiber bundles, have a smooth total space, but are not smooth. This disproves one of the conjectures of the second author and Fern\'andez de Bobadilla.

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Maurício Corrêa, János Kollár. 2026-07-06. Homology fiber bundles of varieties, that are not topological fiber bundles. https://arxiv.org/abs/2607.05603

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