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arXiv · 1509.06028

Special cubic Cremona transformations of $\mathbb{P}^6$ and $\mathbb{P}^7$

Giovanni Staglianò
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Abstract

A famous result of B. Crauder and S. Katz (1989) concerns the classification of special Cremona transformations whose base locus has dimension at most two. Furthermore, they also proved that a special Cremona transformation with base locus of dimension three has to be one of the following: 1) a quinto-quintic transformation of $\mathbb{P}^5$; 2) a cubo-quintic transformation of $\mathbb{P}^6$; or 3) a quadro-quintic transformation of $\mathbb{P}^8$. Special Cremona transformations as in case 1) have been classified by L. Ein and N. Shepherd-Barron (1989), while in our previous work (2013), we classified special quadro-quintic Cremona transformations of $\mathbb{P}^8$. The main aim here is to consider the problem of classifying special cubo-quintic Cremona transformations of $\mathbb{P}^6$, concluding the classification of special Cremona transformations whose base locus has dimension three.

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Giovanni Staglianò. 2015-09-20. Special cubic Cremona transformations of $\mathbb{P}^6$ and $\mathbb{P}^7$. https://doi.org/10.1515/advgeom-2018-0001

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