Doosung Park: Description of mixed motives

Grothendieck invented the category of numerical motives. From this, the abelian category of pure motives can be obtained assuming his conjectures. This category serves as a universal cohomology theory for schemes smooth and projective over a field. It is expected that there is an abelian category of mixed motives, which contains the abelian category of pure motives as a full subcategory and serves as a universal cohomology theory for schemes smooth but not necessarily projective over a field. I will explain how mixed motives looks assuming several conjectures, and I will give some unconditional examples including 2-motives.