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Intersection cohomology and Severis varieties

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 نشر من قبل Davide Franco
 تاريخ النشر 2020
  مجال البحث
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Let $X^{2n}subseteq mathbb{P} ^N$ be a smooth projective variety. Consider the intersection cohomology complex of the local system $R^{2n-1}pi{_*}mathbb{Q}$, where $pi$ denotes the projection from the universal hyperplane family of $X^{2n}$ to ${(mathbb{P} ^N)}^{vee}$. We investigate the cohomology of the intersection cohomology complex $IC(R^{2n-1}pi{_*}mathbb{Q})$ over the points of a Severis variety, parametrizing nodal hypersurfaces, whose nodes impose independent conditions on the very ample linear system giving the embedding in $mathbb{P} ^N$.



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