Canonical stability of 3-folds of general type with pg ≥ 3
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چکیده
We study the canonical stability of a smooth projective 3-fold V of general type. We prove that |5KV | gives a birational map onto its image provided pg ≥ 4. For those V with pg = 3, |6KV | gives a birational map. Known examples show that both the results are optimal.
منابع مشابه
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Let V be a smooth projective 3-fold of general type. Denote by K, a rational number, the self-intersection of the canonical sheaf of any minimal model of V . Actually 1 2 K is called the volume of V . Assume pg(V ) ≥ 2. We show that K 3 ≥ 1 3 , which is a sharp lower bound. Then we classify those V with small K. We also give some new examples with pg = 2 which have maximal canonical stability. ...
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تاریخ انتشار 2008