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Decomposition of log crepant birational morphisms between log terminal surfaces

Shigetaka Fukuda
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Abstract

We prove that every log crepant birational morphism between log terminal surfaces is decomposed into log-flopping type divisorial contraction morphisms and log blow-downs. Repeating these two kinds of contractions we reach a minimal log minimal surface from any log minimal surface.

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Shigetaka Fukuda. 1999-06-22. Decomposition of log crepant birational morphisms between log terminal surfaces. https://arxiv.org/abs/math/9906143

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