Some complements to the Lazard isomorphism
arXiv:0904.3863 · doi:10.1112/S0010437X10004884
Abstract
Lazard showed in his seminal work "Groupes analytiques -adiques" that for rational coefficients continuous group cohomology of -adic Lie-groups is isomorphic to Lie-algebra cohomology. We refine this result in two directions: firstly we extend his isomorphism under certain conditions to integral coefficients and secondly, we show that for algebraic groups, his isomorphism can be realized by differentiating locally analytic cochains.
Final version, to appear in Compositio Mathematica