Résume | Lazard-Serre showed that the continuous cohomology of compact
p-torsionfree p-adic Lie groups, with p-adic coefficients, exhibits
Poincaré duality. A suprisingly subtle point in Lazard's work is the
identification of the relevant twist, or dualizing object. I will
describe another approach to this identification, which also yields more
refined information inaccessible via Lazard's approach. The method is
probably more important than the result: it involves a somewhat
surprising cospecialization map for sheaves in a p-adic context, which
should have other applications as well. |