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arXiv · 1309.0963

A Picard modular fourfold and the Weyl group W(E_6)

Bert van Geemen·Kenji Koike
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Abstract

We study the geometry of a Picard modular fourfold which parametrizes abelian fourfolds of Weil type for the field of cube roots of unity. We find a projective model of this fourfold as a singular, degree ten, hypersurface X in projective 5-space. The Weyl group W(E_6) acts on X and we provide an explicit description of this action. Moreover, we describe various special subvarieties as well as the boundary of X.

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Bert van Geemen, Kenji Koike. 2013-09-04. A Picard modular fourfold and the Weyl group W(E_6). https://arxiv.org/abs/1309.0963

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