Chow rings and modified diagonals

Tuesday, October 7, 2014 -
2:00pm to 3:30pm
Beauville and Voisin proved that decomposable cycles (intersections of divisors) on a projective K3 surface span a 1-dimensional subspace of the (infinite-dimensional) group of 0-cycles modulo rational equivalence. I will address the following question: what is the rank of the group of decomposable 0-cycles of a smooth projective variety? Beauville and Voisin also proved a refinement of the result mentioned above, namely a decomposition (modulo rational equivalence) of the small diagonal in the cube of a K3. Motivated by this result we will discuss modified diagonals and their relation with conjectures of Beauville and Voisin on the Chow ring of hyperkaehler varieties.
Kieran O'Grady
Sapienza University, Rome
Event Location: 
IAS Room S-101