English

On the derived category of 1-motives, I

Algebraic Geometry 2009-09-29 v1

Abstract

We consider the category of Deligne 1-motives over a perfect field k of exponential characteristic p and its derived category for a suitable exact structure after inverting p. As a first result, we provide a fully faithful embedding into an etale version of Voevodsky's triangulated category of geometric motives. Our second main result is that this full embedding "almost" has a left adjoint, that we call \LAlb. Applied to the motive of a variety we thus get a bounded complex of 1-motives, that we compute fully for smooth varieties and partly for singular varieties. As an application we give motivic proofs of Roitman type theorems (in characteristic 0).

Keywords

Cite

@article{arxiv.0706.1498,
  title  = {On the derived category of 1-motives, I},
  author = {Luca Barbieri-Viale and Bruno Kahn},
  journal= {arXiv preprint arXiv:0706.1498},
  year   = {2009}
}