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arXiv · 2012.05327

Relative MMP without Q-factoriality

János Kollár
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Abstract

We consider the minimal model program for varieties that are not Q-factorial. We show that, in many cases, its steps are simpler than expected. In particular, all flips are 1-complemented. The main applications are to log terminal singularities, removing the earlier Q-factoriality assumption from several theorems of Hacon--Witaszek and de~Fernex--Koll\'ar--Xu. Version 2: many small changes.

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János Kollár. 2020-12-09. Relative MMP without Q-factoriality. https://arxiv.org/abs/2012.05327

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