4 papers
Integrality of Hecke eigenvalues and the growth of Hecke fields
Kenji Sakugawa, Shingo Sugiyama
We prove that Hecke eigenvalues for any Hilbert and Siegel modular forms are algebraic integers. Our method does not rely on cohomologicality nor Galois representations. We apply t…
Symmetric multiple Eisenstein series
Takashi Hara, Kenji Sakugawa, Koji Tasaka
In this paper, we introduce the symmetric multiple Eisenstein series, a variant of the multiple Eisenstein series. As a fundamental result, we show that they satisfy the linear shu…
On the infinite Frobenius action on de Rham fundamental groups of affine curves
Kenji Sakugawa
We study the action of the infinite Frobenius on the de Rham fundamental groups of affine curves defined over $\bfR$. As an application, we compute extension classes of real mixed…
The depth-weight compatibility on the motivic fundamental Lie algebra and the Bloch-Kato conjecture for modular forms
Kenji Sakugawa
Let be a prime number and let be a continuous representation of on a finite dimensional -vector space, which is…