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arXiv · 2310.02764

On the direct image of the adjoint line bundle

Indranil Biswas·Fatima Laytimi·D. S. Nagaraj·Werner Nahm
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Abstract

We give an algebraic-geometric proof of the fact that for a smooth fibration $\pi: X \longrightarrow Y$ of projective varieties, the direct image $\pi_*(L\otimes K_{X/Y})$ of the adjoint line bundle of an ample (respectively, nef and $\pi$-strongly big) line bundle $L$ is ample (respectively, nef and big).

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Indranil Biswas, Fatima Laytimi, D. S. Nagaraj, Werner Nahm. 2023-10-04. On the direct image of the adjoint line bundle. https://arxiv.org/abs/2310.02764

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