Algebraic Cycles on Todorov Surfaces of Type (2, 12)

Cycle 32th Oral Defence of the Phd Thesis

June 19, 2020
Versione stampabile

Venue:​ The event will take place online through the ZOOM platform. To get the access codes please contact Prof. Claudio Fontanari (claudio.fontanari [at]
Time: 10.00 a.m.

  • Natascia Zangani - PhD in Mathematics, University of Trento

The influence  of Chow groups on singular cohomology is motivated by classical results by Mumford and Roitman and has been investigated extensively. On the other hand, the converse influence is rather conjectural and it takes place in the framework of the "philosophy of mixed motives'', which is mainly due to Grothendieck, Bloch and Beilinson. In the spirit of exploring this  influence, Voisin formulated in 1996 a conjecture on 0-cycles on the self-product of surfaces of geometric genus one. There are few examples in which Voisin's conjecture has been verified, but it is still open for a general K3 surface.  Our aim is to present a new example in which Voisin's conjecture is true, a family of Todorov surfaces. We give an explicit description of the family  as quotient of complete intersection of four quadrics in P^6. We verify Voisin's conjecture for the family of Todorov surfaces of type (2,12). Our main tool is Voisin's "spreading of cycles'', we use it to establish a relation between 0-cycles on the Todorov surface and on the associated K3 surface. We give a motivic version of this result and some interesting motivic applications.

Supervisors: Robert Laterveer, Claudio Fontanari