# On normal crossings symplectic divisors

 Princeton/IAS Symplectic Geometry Seminar Topic: On normal crossings symplectic divisors Speaker: Aleksey Zinger Affiliation: Stony Brook University Date: Friday, December 12 Time/Room: 1:30pm - 2:30pm/Fine 322, Princeton University

I will describe purely symplectic notions of normal crossings divisor and configuration. They are compatible with the existence of the desired auxiliary almost Kahler structures, provided existence" is suitably interpreted. These notions lead to a multifold version of Gompf's symplectic sum construction. They also imply that Brett Parker's work on exploded manifolds concerns a multifold version of the usual symplectic sum (or degeneration) formula for Gromov-Witten invariants. This talk will be about general symplectic topology, not GW-invariants. This is joint work with Mark McLean and Mohammad Tehrani.