Boundedness of Fano threefolds with log-terminal singularities of given index

Alexandr Borisov

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arXiv · math/9910044

Boundedness of Fano threefolds with log-terminal singularities of given index

Alexandr Borisov

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Abstract

We prove the boundedness theorem for Fano threefolds with log-terminal singularities of any fixed index. This is an improvement of our earlier result, where we required additionally that the variety is Q-factorial, with Picard number 1. The new ideas of the paper include the following. 1. Using Alexeev Minimal Model program with suitable boundary to find horizontal extremal contractions. 2. Using Kollár's effective Base Point Freeness theorem. 3. Using Kawamata's result on the length of extremal curves with suitable boundary to avoid gluing curves in some cases.

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BibTeX RIS

Alexandr Borisov. 2005-02-24. Boundedness of Fano threefolds with log-terminal singularities of given index. https://arxiv.org/abs/math/9910044

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