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arXiv · 1711.06218

The indeterminacy locus of the Voisin map

Giosuè Emanuele Muratore
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Abstract

Beauville and Donagi proved that the variety of lines $F(Y)$ of a smooth cubic fourfold $Y$ is a hyperk\"ahler variety. Recently, C. Lehn, M.Lehn, Sorger and van Straten proved that one can naturally associate a hyperK\"ahler variety $Z(Y)$ to the variety of twisted cubics on $Y$. Then, Voisin defined a degree 6 rational map $\psi:F(Y)\times F(Y)\dashrightarrow Z(Y)$. We will show that the indeterminacy locus of $\psi$ is the locus of intersecting lines.

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Giosuè Emanuele Muratore. 2017-11-16. The indeterminacy locus of the Voisin map. https://doi.org/10.1007/s13366-019-00454-x

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