The greatest use of the HahnBanach theorem ever
The greatest use of the HahnBanach theorem ever

Rohil Prasad, Princeton University
Fine Hall 314
InPerson Talk
Let F denote a smooth pdimensional foliation of a manifold M. Nearly fifty years ago, Dennis Sullivan used the HahnBanach theorem to demonstrate a duality between closed pdimensional currents tangent to F and closed pdimensional forms positive on the leaves of F. This turns out to be very useful.