4 papers · 1 filter
Dimension of the motivic Galois group of a 1-motive
Cristiana Bertolin
We compute the dimension of the motivic Galois group of a 1-motive M defined over the field of complex numbers, expressing it explicitly in terms of the rank of the multiplicative…
1-motives and admissible variations of mixed Hodge structures
Cristiana Bertolin
Let S be a connected scheme smooth and of finite type over the field of complex numbers. To every 1-motive over S, André associated the enriched Hodge realization given by a torsio…
The group law of Picard stacks via matrices
Cristiana Bertolin, Federica Galluzzi
Let S be a site. We show that the 2-stack of strictly commutative Picard stacks over S is algebraic, i.e. it is 2-equivalent to the 2-stack of 2-algebras for an adequate algebraic…
A note on divisorial correspondences of extensions of abelian schemes by tori
Cristiana Bertolin, Federica Galluzzi
Let S be a locally noetherian scheme and consider two extensions G_1 and G_2 of abelian S-schemes by S-tori. In this note we prove that the fppf-sheaf Corr _S(G_1,G_2) of divisoria…