数理談話会

日時：2010年11月18日(木曜日)
　　　 午後3時30分～4時 (ティータイム)
　　　 午後4時～5時 (講演)

場所：数理棟 談話室 (ティータイム)
　　　 図書館３階中セミナー室２ (講演)

概要：
The talk belongs to a relatively new scenario in number theory.
Let K/k be a Galois extension of number fields. The main idea is to borrow
a method of Poincare on automorphic functions to do number theory by
replacing the ring R of holomorphic functions on the upper half plane by the
ring of algebraic integers of K and the modular group G acting on R by the
Galois group of K/k.
It turns out that the index of space of Poincare series in the space of
modular forms ( for a given weight) corresponds to a kind of "index"
involving invariants in ramification theory of Galois extensions.