JGSeminar May 13th

[Rafael Torres]

Date/time/place May 13th/11 am/Room 136


Title: An uncountable family of exotic R^4’s


Speaker: Elisa Vitale (SISSA)



Abstract: It is known that in dimension n \neq 4 there exists a unique smooth structure on R^n up to diffeomorphism. However, in dimension four we can find "exotic" R^4's, smooth 4-manifolds homeomorphic to R^4, but not diffeomorphic to it. In 1985, Robert Gompf showed that the set of exotic structures on R^4 is uncountable. The purpose of this talk is to outline the proof of Gompf's theorem.