activity
20242026
collaborators

8 papers

math.NT2026

Isogeny graphs associated to Moret-Bailly families of supersingular abelian surfaces

Toshiyuki Katsura, Takuya Yamauchi

For an odd prime and any prime , we study finite directed graphs arising from the set of all equivalence classes of Moret-Bailly families of abelian surfaces in cha…

math.NT2026

Harder's conjecture II

Hiraku Atobe, Masataka Chida, Tomoyoshi Ibukiyama +2

Let be a primitive form of weight for , and let be a prime ideal of the Hecke field of . We denote by the Siegel modular group of degree .…

math.NT2026

The -function of the surface parametrizing cuboids

Madoka Horie, Takuya Yamauchi

In this note, we compute the -function of the projective smooth surface over that parametrizes cuboids whose geometric properties are studied in detail by Stoll…

math.NT2025

Regulators on some abelian coverings of minus points

Yusuke Nemoto, Takuya Yamauchi

In this paper, we construct certain rational or integral elements in the motivic cohomology of superelliptic curves which are quotient curves of abelian coverings of

math.NT2025

The non-existence of some Galois representations of moderate dimension in small characteristic

Alexandru Ghitza, Takuya Yamauchi

Refining arguments of Hyunsuk Moon, under the assumption of the Generalized Riemann Hypothesis, we prove the non-existence of irreducible mod 2 Galois representations unramified ou…

math.NT2025

A new theta cycle for and an Edixhoven type theorem

Takuya Yamauchi

In this paper, we investigate a new theta cycle for by using author's theta operators defined in the previous work. In the course of the construction, we also mo…