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arXiv · 1304.2231

Decomposition of direct images of logarithmic differentials

Donu Arapura
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Abstract

The purpose of this note is to give a short proof of a theorem of Kollár that the derived direct image of the canonical sheaf splits into a sum of its cohomology sheaves. This is deduced from a stronger decomposition theorem for direct images of sheaves of logarithmic differentials, together with the weak semistable reduction theorem.

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Donu Arapura. 2013-09-13. Decomposition of direct images of logarithmic differentials. https://arxiv.org/abs/1304.2231

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