Thursday 10 Oct 2013: The Display of a K3-surface with applications to deformation theory
Andreas Langer - University of Exeter
Harrison 103 15:00-16:00
Displays are objects in Frobenius-linear algebra and were introduced to classify p-divisible groups
over a ring R where p is nilpotent. We defined a more general notion of higher displays which arise in many examples
as an additional structure on the crystalline cohomology of a smooth and proper scheme X over R.
In my talk I will exhibit the 2-display associated to a K3-surface X. We can prove an analogue of
Grothendieck-Messing for K3-surfaces: Deformations of X over a PD-neighbourhood correspond uniquely
to isotropic liftings of the Hodge-filtration resp deformations of the 2-display.
This is joint work with Thomas Zink.