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Exts and Vertex Operators

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 نشر من قبل Erik Carlsson
 تاريخ النشر 2017
  مجال البحث
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The direct product of two Hilbert schemes of the same surface has natural K-theory classes given by the alternating Ext groups between the two ideal sheaves in question, twisted by a line bundle. We express the Chern classes of these virtual bundles in terms of Nakajima operators.



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