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arXiv · 0803.1691

Finite generation of the log canonical ring in dimension four

Osamu Fujino
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Abstract

We treat two different topics on the log minimal model program, especially for four-dimensional log canonical pairs. (a) Finite generation of the log canonical ring in dimension four. (b) Abundance theorem for irregular fourfolds. We obtain (a) as a direct consequence of the existence of four-dimensional log minimal models by using Fukuda's theorem on the four-dimensional log abundance conjecture. We can prove (b) only by using traditional arguments. More precisely, we prove the abundance conjecture for irregular $(n+1)$-folds on the assumption that the minimal model conjecture and the abundance conjecture hold in dimension $\leq n$.

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Osamu Fujino. 2008-03-12. Finite generation of the log canonical ring in dimension four. https://doi.org/10.1215/0023608x-2010-010

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