Remarks on Gorenstein Terminal Fourfold Flips
Vol. 5 (1998), No. 1, Page 149--164.
Takagi, Hiromichi
Remarks on Gorenstein Terminal Fourfold Flips
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Abstract:
We prove that for any flipping contraction from a Gorenstein terminal $4$-fold, a general hyperplane section which contains the exceptional locus has only canonical singularities. Based on this fact and using Ran's theorem, we prove the existence of the flip of a flipping contraction from a Gorenstein terminal $4$-fold whose general hyperplane section has only isolated canonical singularities and exceptional locus is irreducible. Furthermore we classify such flipping contractions and flips.
Keywords: flip, extremal ray, minimal model
Mathematics Subject Classification (1991): Primary 14E30; Secondary 14J35, 14M05
Mathematical Reviews Number: MR1617075
Received: 1997-03-31
