A sharp bilinear restriction estimate for paraboloids

Recently Wolff [W3] obtained a sharp L-2 bilinear restriction theorem for bounded subsets of the cone in general dimension. Here we adapt the argument of Wolff to also handle subsets of "elliptic surfaces" such as paraboloids. Except for an endpoint, this answers a conjecture of Machedon and Klainerman, and also improves upon the known restriction theory for the paraboloid and sphere.