トポロジー火曜セミナー

過去の記録 ~12/01次回の予定今後の予定 12/02~

開催情報 火曜日 17:00~18:30 数理科学研究科棟(駒場) 056号室
担当者 河澄 響矢, 北山 貴裕, 逆井卓也, 葉廣和夫
セミナーURL https://park.itc.u-tokyo.ac.jp/MSF/topology/TuesdaySeminar/index.html

2025年11月11日(火)

9:30-10:30   オンライン開催
参加を希望される場合は、下記URLから参加登録を行って下さい。
Richard Hain 氏 (Duke University)
Mapping class group actions on the homology of configuration spaces (ENGLISH)
[ 講演概要 ]
The action of the mapping class group of a surface S on the homology of the space F_n(S) of ordered configurations of n points in S is well understood when S has genus 0, but is not very well understood when S has positive genus. In this talk I will report on joint work with Clément Dupont (Montpellier) in the case where S is a surface of finite type of genus at least 2. We give a strong lower bound on the size of the Zariski closure of the image of the Torelli and mapping class groups in the automorphism group of the degree n cohomology of F_n(S). Our main tools are Hodge theory and the Goldman Lie algebra of the surface, which is the free abelian group generated by the conjugacy classes in the fundamental group of S.
[ 参考URL ]
https://park.itc.u-tokyo.ac.jp/MSF/topology/TuesdaySeminar/index_e.html