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arXiv · 1401.8188

On the Hilbert scheme of degeneracy loci of twisted differential forms

Fabio Tanturri
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Abstract

We prove that, for 3 < m < n-1, the Grassmannian of m-dimensional subspaces of the space of skew-symmetric forms over a vector space of dimension n is birational to the Hilbert scheme of the degeneracy loci of m global sections of Omega(2), the twisted cotangent bundle on P^{n-1}. For 3=m<n-1 and n odd, this Grassmannian is proved to be birational to the set of Veronese surfaces parametrized by the Pfaffians of linear skew-symmetric matrices of order n.

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Fabio Tanturri. 2014-01-31. On the Hilbert scheme of degeneracy loci of twisted differential forms. https://doi.org/10.1090/tran%2F6637

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