On mixed-$\omega$-sheaves

Osamu Fujino

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arXiv · 1908.00171

On mixed-$\omega$-sheaves

Osamu Fujino

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Abstract

We introduce the notion of mixed-$\omega$-sheaves and use it for the study of a relative version of Fujita's freeness conjecture. It is related to the Iitaka conjecture. We note that the notion of mixed-$\omega$-sheaves is a generalization of that of Nakayama's $\omega$-sheaves in some sense. One of the main motivations of this paper is to make Nakayama's theory of $\omega$-sheaves more accessible and make it applicable to the study of log canonical pairs.

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Osamu Fujino. 2019-08-01. On mixed-$\omega$-sheaves. https://arxiv.org/abs/1908.00171

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