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On the canonical threefolds with strictly nef anticanonical divisors

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 نشر من قبل Hokuto Uehara
 تاريخ النشر 1999
  مجال البحث
والبحث باللغة English
 تأليف H. Uehara




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Any ample Cartier divisor D on a projective variety X is strictly nef (i.e. D.C>0 for any effective curve C on X). In general, the converse statement does not hold. But this is conjectured to be true for anticanonical divisors. The present paper establishes this fact for normal complex projective threefolds with canonical singularities. This result extends several previously known special cases. The proof rests mainly on sophisticated techniques of three dimensional birational geometry developed in the last two decades.



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