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Cox rings over nonclosed fields

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 نشر من قبل Ulrich Derenthal
 تاريخ النشر 2014
  مجال البحث
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We give a definition of Cox rings and Cox sheaves for varieties over nonclosed fields that is compatible with torsors under quasitori, including universal torsors. We study their existence and classification, we make the relation to torsors precise, and we present arithmetic applications.



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