Threefold extremal curve germs with one non-Gorenstein point

Sh. Mori ; Yu. G. Prokhorov

Izvestiya. Mathematics , Tome 83 (2019) no. 3, pp. 565-612.

Résumé

An extremal curve germ is the analytic germ of a threefold with terminal singularities along a reduced complete curve admitting a contraction whose fibres have dimension at most one. The aim of the present paper is to review the results concerning contractions whose central fibre is irreducible and contains only one non-Gorenstein point.

Détail

Keywords: extremal curve germ, terminal singularity, canonical divisor, blow-up, flip, $Q$-conic bundle.
Mots-clés : birational map

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