12 citations · 55 across the 36 of their papers we have counts for
39 papers
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…
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 …
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…
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…
The residual monodromy for the Dwork family in even characteristic and its applications to Galois representations
Takuya Yamauchi
We study the residual monodromy representations associated to the Dwork family in characteristic two. Various applications involving 2-adic and mod 2 Galois representations are dis…
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 .…
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…
Isogeny graphs on superspecial abelian varieties: Eigenvalues and Connection to Bruhat-Tits buildings
Yusuke Aikawa, Ryokichi Tanaka, Takuya Yamauchi
We study for each fixed integer , for all primes and with , finite regular directed graphs associated with the set of equivalence classes of …
Harder's conjecture I
Hiraku Atobe, Masataka Chida, Tomoyoshi Ibukiyama +2
Let be a primitive form with respect to . Then we propose a conjecture on the congruence between the Klingen-Eisenstein lift of the Duke-Imamoglu-Ikeda lift of and…
A remark on conductor, depth and principal congruence subgroups
Michitaka Miyauchi, Takuya Yamauchi
In this paper we study a relation between conductor, depth, and the level of principal congruence subgroups for irreducible admissible representations of for a non-…
On finiteness theorems for automorphic forms
Takuya Yamauchi
In this paper, for any Shimura datum satisfying reasonable conditions so that many interesting cases satisfy, we prove some finiteness theorems for any graded vec…
Equidistribution theorems for holomorphic Siegel cusp forms of general degree: the level aspect
Henry H. Kim, Satoshi Wakatsuki, Takuya Yamauchi
We prove equidistribution theorems for a family of holomorphic Siegel cusp forms of general degree in the level aspect. Our main contribution is to estimate unipotent contributions…
Transfers of some Hecke elements for possibly ramified base change in GL_n
Takuya Yamauchi
In this paper we prove an explicit matching theorem for some Hecke elements in the case of (possibly ramified) cyclic base change for general linear groups over local fields of cha…
Period of the Ikeda type lift for
Hidenori Katsurada, Henry H. Kim, Takuya Yamauchi
In our previous work, he second and the third named authors constructed the Ikeda type lift for the exceptional group from an elliptic modular cusp form. In this paper, w…
Automorphy of mod 2 Galois representations associated to certain genus 2 curves over totally real fields
Alexandru Ghitza, Takuya Yamauchi
Let be a genus two hyperelliptic curve over a totally real field . We show that the mod 2 Galois representation $\barρ_{C,2}\colon\mathrm{Gal}(\bar{F}/F)\to \mathrm{GSp}_4(\…
Automorphy of mod 2 Galois representations associated to the quintic Dwork family and reciprocity of some quintic trinomials
Nobuo Tsuzuki, Takuya Yamauchi
In this paper, we determine mod Galois representations associated to the mirror motives of rank…
Serre weights for over totally real fields
Takuya Yamauchi
We prove the existence of a potentially diagonalizable lift of a given automorphic mod Galois representation $\overlineρ:{\rm Gal}(\overline{F}/F)\longrightarrow {\rm GSp}_4(\o…
Congruences of Siegel Eisenstein series of degree two
Takuya Yamauchi
In this paper we study congruences between Siegel Eisenstein series and Siegel cusp forms for Sp_4(Z).
Non-vanishing of Miyawaki type lift
Henry H. Kim, Takuya Yamauchi
Miyawaki type lifts are kinds of Langlands functorial lifts and a special case was first conjectured by Miyawaki and proved by Ikeda for Siegel cusp forms. Since then, such a lift…
A reformulation of the Siegel series and intersection numbers
Sungmun Cho, Takuya Yamauchi
In this paper, we will explain a conceptual reformulation and inductive formula of the Siegel series. Using this, we will explain that both sides of the local intersection multipli…
Equidistribution theorems for holomorphic Siegel modular forms for ; Hecke fields and -level density
Henry H. Kim, Satoshi Wakatsuki, Takuya Yamauchi
This paper is a continuation of the author's previous wotk. We supplement four results on a family of holomorphic Siegel cusp forms for . First, we improve the re…
Derivatives of Eisenstein series of weight 2 and intersections of modular correspondences
Sungmun Cho, Shunsuke Yamana, Takuya Yamauchi
We give a formula for certain values and derivatives of Siegel series and use them to compute Fourier coefficients of derivatives of the Siegel Eisenstein series of weight g/2 and…
Higher level cusp forms on the exceptional group of type
Henry H. Kim, Takuya Yamauchi
By using new techniques with the degenerate Whittaker functions found by Ikeda-Yamana, we construct higher level cusp form on , called Ikeda type lift, from any Hecke cusp…
An explicit formula for the extended Gross-Keating datum of a quadratic form
Sungmun Cho, Tamotsu Ikeda, Hidenori Katsurada +2
In this paper, we give a formula for the extended Gross-Keating datum of a quadratic form defined over a finite extension of (for ) or a finite unramified exten…