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arXiv · 2608.18646

Quadratic Cremona transformations of $\mathbb{P}^4$

Gianluca Grassi·Alex Massarenti
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Abstract

We prove that $Bir_2(\mathbb{P}^4)$ has exactly nine irreducible components and that the locus of transformations with zero-dimensional base scheme is irreducible.

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Gianluca Grassi, Alex Massarenti. 2026-08-19. Quadratic Cremona transformations of $\mathbb{P}^4$. https://arxiv.org/abs/2608.18646

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