SIMULTANEOUS Q-FACTORIALIZATION OF DIVISORS AND APPLICATIONS TO 3-FOLD DIVISORIAL CONTRACTIONS THAT CONTRACT A DIVISOR ONTO A CURVE THROUGH A cD5 SINGULARITY
نویسنده
چکیده
Let Γ ⊂ X be a smooth curve on a 3-fold. In this paper we classify terminal divisorial contractions E ⊂ Y −→ Γ ⊂ X contracting an irreducible surface E onto Γ, in the case when the general section of X containing Γ has D5 type singularities. In doing so we consider the problem of existence of MMP in families of canonical 3-folds, and we get results about existence of simultaneous Q-factorialisation of a family of divisors.
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