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Powers of the theta divisor and relations in the tautological ring

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 نشر من قبل Dmitry Zakharov
 تاريخ النشر 2016
  مجال البحث
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We show that the vanishing of the $(g+1)$-st power of the theta divisor on the universal abelian variety $mathcal{X}_g$ implies, by pulling back along a collection of Abel--Jacobi maps, the vanishing results in the tautological ring of $mathcal{M}_{g,n}$ of Looijenga, Ionel, Graber--Vakil, and Faber--Pandharipande. We also show that Pixtons double ramification cycle relations, which generalize the theta vanishing relations and were recently proved by the first and third authors, imply Theorem~$star$ of Graber and Vakil, and we provide an explicit algorithm for expressing any tautological class on $overline{mathcal{M}}_{g,n}$ of sufficiently high codimension as a boundary class.



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