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Threefold extremal contractions of type (IIA). I

Izvestiya. Mathematics. 2016. Vol. 80. No. 5. P. 884–909.
Mori S., Prokhorov Y.

Let (X,C) be a germ of a threefold X with terminal singularities along an irreducible reduced complete curve C with a contraction f:(X,C)→(Z,o) such that C=f^{−1}(o)_red and −KX is ample. Assume that (X,C) contains a point of type (IIA) and that a general member H∈|OX| containing C is normal. We classify such germs in terms of H.

Priority areas: mathematics
Language: English
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Keywords: terminal singularityтерминальная особенностьthreefoldтрехмерное многообразие
Publication based on the results of:
Алгебраическая геометрия и ее приложения: Производные категории; Гомологические и мотивные методы в некоммутативной геометрии; Специальные многообразия; Классическая геометрия; Геометрическая теория представлений; Арифметическая геометрия (2016)
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