Weil-etale cohomology and Frobenius rigidity

開催日時
2025/12/12 金 13:00 - 14:30
場所
RIMS006号室
講演者
Thomas Geisser
講演者所属
立教大学
概要

For varieties over finite fields, one can improve some cohomology theories (like motivic cohomology) if one replaces descent by the Galois group of the finite field by descent by its Weil group. This raises the question to what extent do the motivic cohomology groups and etale motivic cohomology groups on the choice of an algebraically closed field. I will discuss what is known in this direction and what is still open.