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arXiv · 1608.03416

On fields of definition of components of the Siegel supersingular locus

Chia-Fu Yu
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Abstract

Recently Ibukiyama proves an explicit formula for the number of certain non-principal polarizations on a superspecial abelian surface, extending his earlier work with Katsura for principal polarizations [Compos. Math. 1994]. As a consequence of Ibukiyama's formula, there exists a geometrically irreducible component of the Siegel supersingular locus which is defined over the prime finite field. In this note we give a direct proof of this result.

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Chia-Fu Yu. 2016-08-11. On fields of definition of components of the Siegel supersingular locus. https://arxiv.org/abs/1608.03416

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