3 papers
math.AG2018
Representations of Affine Group Schemes Over General Rings
Giulia Battiston, Matthieu Romagny
Among all affine, flat, finitely presented group schemes, we focus on those that are pure, this includes all groups which are extensions of a finite locally free group by a group w…
math.AG2018
The normal hull and commutator group for nonconnected group schemes
Giulia Battiston
In this short note, we prove that there is a well behaved notion of normal hull for smooth algebraic group schemes over a field and that the commutator group is well define…
math.AG2016
The homotopy sequence for regular singular stratified bundles
Giulia Battiston, Lars Kindler
A separable, proper morphism of varieties with geometrically connected fibers induces a homotopy exact sequence relating the étale fundamental groups of source, target and fiber. E…