Boundedness of Fano threefolds with log-terminal singularities of given index
Alexandr Borisov
备注：
This is the final version of the paper, mathematically equivalent to the one that appeared in the J. Math. Sci. Univ. Tokyo. It corrects a small error in the first version
发表信息：
J. Math. Sci. Univ. Tokyo 8 (2001), no. 2, 329--342
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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