Department of Mathematics

Kazuki Yamada

  (山田 一紀)

Profile Information

Affiliation
Assistant Professor, Department of Mathematics, Faculty of Science , Gakushuin University
Degree
Doctor of Science(Mar, 2020, Keio University)

Researcher number
20896683
J-GLOBAL ID
201401090887066393
researchmap Member ID
B000241714

Research Areas

 1

Papers

 6
  • Kenichi Bannai, Hohto Bekki, Kei Hagihara, Tatsuya Ohshita, Kazuki Yamada, Shuji Yamamoto
    Advances in Mathematics, 448 Paper No. 109716, Jun, 2024  Peer-reviewed
  • Kenichi Bannai, Kei Hagihara, Kazuki Yamada, Shuji Yamamoto
    Transactions of the American Mathematical Society, Series B, 10(19) 613-635, May 2, 2023  
    <p>It is known that the special values at nonpositive integers of a Dirichlet -function may be expressed using the generalized Bernoulli numbers, which are defined by a generating function. The purpose of this article is to consider the generalization of this classical result to the case of Hecke -functions of totally real fields. Hecke -functions may be expressed canonically as a finite sum of zeta functions of Lerch type. By combining the non-canonical multivariable generating functions constructed by Shintani [J. Fac. Sci. Univ. Tokyo Sect. IA Math. 23 (1976), pp. 393–417], we newly construct a canonical class, which we call the Shintani generating class, in the equivariant cohomology of an algebraic torus associated to the totally real field. Our main result states that the specializations at torsion points of the derivatives of the Shintani generating class give values at nonpositive integers of the zeta functions of Lerch type. This result gives the insight that the correct framework in the higher dimensional case is to consider higher equivariant cohomology classes instead of functions.</p>
  • Kenichi Bannai, Kei Hagihara, Kazuki Yamada, Shuji Yamamoto
    Journal für die reine und angewandte Mathematik (Crelles Journal), 2022(791) 53-87, Oct 1, 2022  Peer-reviewed
    Abstract The purpose of this article is to newly define the p-adic polylogarithmas an equivariant class in the cohomology of a certain infinite disjoint union of algebraic toriassociated to a totally real field.We will then express the special values of p-adic L-functions interpolatingnonpositive values of Hecke L-functions of the totally real field in terms ofspecial values of these p-adic polylogarithms.
  • Veronika Ertl, Kazuki Yamada
    Rendiconti del Seminario Matematico della Universita di Padova, 145 213-291, May, 2021  Peer-reviewed
  • Kenichi Bannai, Kei Hagihara, Kazuki Yamada, Shuji Yamamoto
    Mathematische Zeitschrift, 296(3-4) 1787-1817, Dec, 2020  Peer-reviewed

Misc.

 3

Presentations

 27

Teaching Experience

 9

Professional Memberships

 1

Research Projects

 3