Del Pezzo quintics as equivariant compactifications of vector groups

Adrien Dubouloz; Takashi Kishimoto; Pedro Montero

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arXiv · 2209.04152

Del Pezzo quintics as equivariant compactifications of vector groups

Adrien Dubouloz·Takashi Kishimoto·Pedro Montero

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Abstract

We study faithful actions with a dense orbit of abelian unipotent groups on quintic del Pezzo varieties over a field of characteristic zero. Such varieties are forms of linear sections of the Grassmannian of planes in a 5-dimensional vector space. We characterize which smooth forms admit these types of actions and show that in case of existence, the action is unique up to equivalence by automorphisms. We also give a similar classification for mildly singular quintic del Pezzo threefolds and surfaces.

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Adrien Dubouloz, Takashi Kishimoto, Pedro Montero. 2022-09-09. Del Pezzo quintics as equivariant compactifications of vector groups. https://arxiv.org/abs/2209.04152

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