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A support theorem for nested Hilbert schemes of planar curves

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 نشر من قبل Camilla Felisetti
 تاريخ النشر 2018
  مجال البحث
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 تأليف Camilla Felisetti




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Consider a family of integral complex locally planar curves. We show that under some assumptions on the basis, the relative nested Hilbert scheme is smooth. In this case, the decomposition theorem of Beilinson, Bernstein and Deligne asserts that the pushforward of the constant sheaf on the relative nested Hilbert scheme splits as a direct sum of shifted semisimple perverse sheaves. We will show that no summand is supported in positive codimension.

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