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Subadjunction for quasi-log canonical pairs and its applications

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 Added by Osamu Fujino
 Publication date 2020
  fields
and research's language is English
 Authors Osamu Fujino




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We establish a kind of subadjunction formula for quasi-log canonical pairs. As an application, we prove that a connected projective quasi-log canonical pair whose quasi-log canonical class is anti-ample is simply connected and rationally chain connected. We also supplement the cone theorem for quasi-log canonical pairs. More precisely, we prove that every negative extremal ray is spanned by a rational curve. Finally, we treat the notion of Mori hyperbolicity for quasi-log canonical pairs.



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