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The stable hyperelliptic locus in genus 3: An application of Porteous Formula

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 نشر من قبل Eduardo Esteves
 تاريخ النشر 2013
  مجال البحث
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 تأليف Eduardo Esteves




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We compute the class of the closure of the locus of hyperelliptic curves in the moduli space of stable genus-3 curves in terms of the tautological class $lambda$ and the boundary classes $delta_0$ and $delta_1$. The expression of this class is known, but here we compute it directly, by means of Porteous Formula, without resorting to blowups or test curves.



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