UNEXPECTED SUBGROUP SCHEMES OF PGL 2,k IN CHARACTERISTIC 2
Language
en
Document de travail - Pré-publication
English Abstract
If the characteristic of a field $k$ is odd any infinitesimal group scheme of $PGL_{2,k}$ lifts to $SL_{2,k}$. In this paper, we prove that this is not true in characteristic $2$ and we give a complete description, up to ...Read more >
If the characteristic of a field $k$ is odd any infinitesimal group scheme of $PGL_{2,k}$ lifts to $SL_{2,k}$. In this paper, we prove that this is not true in characteristic $2$ and we give a complete description, up to isomorphism, of infinitesimal unipotent subgroup schemes of $PGL_{2,k}$. Also, the infinitesimal trigonalizable case is considered.Read less <
English Keywords
infinitesimal group schemes
actions of group schemes
Origin
Hal imported