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Representation theory and the cycle map of a classifying space

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 نشر من قبل Masaki Kameko
 تاريخ النشر 2016
  مجال البحث
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 تأليف Masaki Kameko




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We compute the Chern subgroup of the 4-th integral cohomology group of a certain classifying space and show that it is a proper subgroup. Such a classifying space gives us new counterexamples for the integral Hodge and Tate conjectures modulo torsion.



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