Ryosuke Shimada

collaborators

4 papers

math.NT2026

The number of Ekedahl-Oort strata intersecting the supersingular locus in the Siegel modular variety

Ryosuke Shimada

Let $N_{g}$ be the number of Ekedahl-Oort strata intersecting the supersingular locus in the Siegel modular variety. We prove that $N_{g} \sim 2^{g - 1}$ as $g \to \infty$ .

math.AG2026

Some generalizations of Oort's conjecture

Ryosuke Shimada, Teppei Takamatsu

For a prime $p \geq 5$ , let $S_{g}$ be the moduli space over $F_{p}$ of $g$ -dimensional principally polarized supersingular abelian varieties. We show that e…

math.AG2024

On the Supersingular Locus of the $GU (2, n - 2)$ Shimura Variety

Ryosuke Shimada

We study the supersingular locus of a reduction at an inert prime of the Shimura variety attached to $GU (2, n - 2)$ . More concretely, we decompose the supersingular locus int…

math.AG2024

On the supersingular locus of the Siegel modular variety of genus 3 or 4

Ryosuke Shimada, Teppei Takamatsu

We study the supersingular locus of the Siegel modular variety of genus 3 or 4. More concretely, we decompose the supersingular locus into a disjoint union of the product of a Deli…

The number of Ekedahl-Oort strata intersecting the supersingular locus in the Siegel modular variety

Some generalizations of Oort's conjecture

On the Supersingular Locus of the GU(2,n−2) Shimura Variety

On the supersingular locus of the Siegel modular variety of genus 3 or 4

On the Supersingular Locus of the $GU (2, n - 2)$ Shimura Variety