10 citations · 30 across the 16 of their papers we have counts for
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Partial Hasse invariants for Shimura varieties of Hodge-type
Naoki Imai, Jean-Stefan Koskivirta
For a connected reductive group over a finite field, we define partial Hasse invariants on the stack of -zip flags. We obtain similar sections on the flag space of Shimura v…
Normalization of closed Ekedahl-Oort strata
Jean-Stefan Koskivirta
We apply our theory of partial flag spaces developed in previous articles to study a group-theoretical generalization of the canonical filtration of a truncated Barsotti-Tate group…
Stratifications of flag spaces and functoriality
Wushi Goldring, Jean-Stefan Koskivirta
We define quotient stacks of "zip flags". They form towers above the stack of -zips introduced by Moonen, Pink, Wedhorn and Ziegler. We define a stratification on the stack of z…
Sections of the Hodge bundle over Ekedahl-Oort strata of Shimura varieties of Hodge type
Jean-Stefan Koskivirta
We construct canonical non-vanishing global sections of powers of the Hodge bundle on each Ekedahl-Oort stratum of a Hodge type Shimura variety. In particular we recover the quasi-…
Generalized mu-ordinary Hasse invariants
Jean-Stefan Koskivirta, Torsten Wedhorn
We construct canonical Hasse invariants for arbitrary Shimura varieties of Hodge type for the mu-ordinary locus.
Congruence relations for Shimura varieties associated to unitary groups
Jean-Stefan Koskivirta
We prove the congruence relation for the mod-p reduction of Shimura varieties associated to a unitary similitude group GU(n-1,1), when p is inert and n odd. When n is even, this re…