Journal of Algebraic Geometry

Ekedahl-Oort strata contained in the supersingular locus and Deligne-Lusztig varieties

Author(s): Shushi Harashita
Journal: J. Algebraic Geom.
Posted: August 17, 2009
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Abstract: We study the moduli space of principally polarized abelian varieties over fields of positive characteristic. In this paper we describe certain unions of Ekedahl-Oort strata contained in the supersingular locus in terms of Deligne-Lusztig varieties. As a corollary we show that each Ekedahl-Oort stratum contained in the supersingular locus is reducible except possibly for small

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Shushi Harashita
Affiliation: Institute for the Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwanoha Kashiwa-shi Chiba 277-8582 Japan
Email: harasita@ms.u-tokyo.ac.jp

PII: S 1056-3911(09)00519-0
Received by editor(s): March 10, 2008
Received by editor(s) in revised form: June 13, 2008
Posted: August 17, 2009
Additional Notes: This research is partially supported by JSPS Research Fellowship for Young Scientists.
Dedicated: Dedicated to Professor Tomoyoshi Ibukiyama on his 60th birthday

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