Séminaire TNGA : Kazuki Yamada

Le séminaire commencera exceptionnellement à 14h30.

Orateur : Kazuki Yamada (Gakushuin University)

Titre : Log rigid fundamental groups

Résumé : For semistable log schemes over a field of characteristic p, several cohomology theories can be considered depending on the choice of a base ring and a log structure on it.

Furthermore, for each cohomology theory, a fundamental group is defined as the Tannaka dual of the category of coefficient sheaves, and each plays a different role.

As a result of comparing these fundamental groups, I would like to talk about the following three theorems:

1). Homotopy exact sequence with respect to monodromy,

2). Homotopy exact sequence with respect to Frobenius,

3). Hyodo–Kato isomorphism for fundamental groups.