T&G: Alex Pieloch (Columbia), Sections and unirulings of families over the projective line

Date: 
Tue, 12/04/202218:00-19:00
Location: 
Zoom
We will discuss the existence of rational (multi)sections 
and unirulings for projective families f: X -> CP^1 with at most two 
singular fibres.  In particular, we will discuss two ingredients that 
are used to construct the above algebraic curves.  The first is local 
symplectic cohomology groups associated to compact subsets of convex 
symplectic domains.  The second is a degeneration to the normal cone 
argument that allows one to produce closed curves in X from open 
curves (which are produced using local symplectic cohomology) in the 
complement of X by a singular fibre.