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arXiv · 2401.17684

On the direct image of the adjoint big and nef line bundles

Yuta Watanabe·Yongpan Zou
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Abstract

We investigate the positivity properties of the direct image $f_{\ast}(K_{X/Y} \otimes L)$ of the adjoint line bundle associated with a big and nef line bundle $L$, under a smooth fibration $f: X\to Y$ between projective varieties. We show that the vector bundle $f_{\ast}(K_{X/Y} \otimes L)$ is big.

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Yuta Watanabe, Yongpan Zou. 2024-01-31. On the direct image of the adjoint big and nef line bundles. https://arxiv.org/abs/2401.17684

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