activity
20222025
collaborators

7 papers

math.NT2025

On the local equivariant Tamagawa number conjecture for Tate motives

Mahiro Atsuta, Naoto Dainobu, Takenori Kataoka

The local equivariant Tamagawa number conjecture (local ETNC) for a motive predicts a precise relationship between the local arithmetic complex and the root numbers which appear in…

math.NT2024

On -adic -functions of elliptic curves and the ideal class groups of the division fields

Naoto Dainobu

Let be an elliptic curve defined over and be or an imaginary quadratic field with certain conditions. In this article, we study the ideal class gr…

math.NT2023

Ideal class groups of division fields of elliptic curves and everywhere unramified rational points

Naoto Dainobu

Let be an elliptic curve over , an odd prime number and a positive integer. In this article, we investigate the ideal class group $\mathrm{Cl}(\mathbb{Q}(E[…

math.NT2022

Elliptic analogue of irregular prime numbers for the -division fields of the curves

Naoto Dainobu, Yoshinosuke Hirakawa, Hideki Matsumura

A prime number is said to be irregular if it divides the class number of the -th cyclotomic field . In this paper, we study…

math.NT2022

On an explicit reciprocity law in local class field theory via -modules

Naoto Dainobu

Let be an unramified extension of and the group of -th root of unity for a fixed integer . In this paper, we give an explicit formul…

math.NT2022

Ideal class groups of number fields associated to modular Galois representations

Naoto Dainobu

Let be an odd prime number and a modular form. We consider the -valued Galois representation attached to and its twist by the qua…