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arXiv · 2608.10219

A criterion for associated bundles and the weak Beauville--Bogomolov decomposition

Yang Zhang
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Abstract

We give a criterion for a fibration to be an associated fibre bundle. As an application, we show that, under suitable singularity and Cartier-index assumptions, any surjective fibration $X \rightarrow Y$ with nef $-K_{X/Y}$ is an associated fibre bundle. From this, we also deduce a weak Beauville--Bogomolov decomposition for varieties with nef anticanonical divisor.

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Yang Zhang. 2026-08-10. A criterion for associated bundles and the weak Beauville--Bogomolov decomposition. https://arxiv.org/abs/2608.10219

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