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arXiv · 2207.00833

Double EPW-sextics with actions of A7 and irrational GM threefolds

Simone Billi·Tomasz Wawak
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Abstract

We construct two examples of projective hyper-K\"ahler fourfolds of K3[2]-type with an action of the alternating group A7, making them some of the most symmetric hyper-K\"ahler fourfolds. They are realized as so called double EPW sextics and this allows us to construct an explicit family of irrational Gushel-Mukai threefolds.

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Simone Billi, Tomasz Wawak. 2022-07-02. Double EPW-sextics with actions of A7 and irrational GM threefolds. https://arxiv.org/abs/2207.00833

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