Niko Naumann

Niko Naumann works in arithmetic geometry and homotopy theory. With Annette Huber and Guido Kings, he refined the Lazard isomorphism, extending a comparison between continuous group cohomology and Lie algebra cohomology to integral coefficients under suitable hypotheses.^[ref]

The distinction between integral and rational coefficients matters: tensoring with ${\mathbb{Q}}_p$ can discard torsion elements, so a rational comparison does not automatically recover integral information. The same work also treats analytic cochains over finite extensions of ${\mathbb{Q}}_p$. Naumann's author page lists arithmetic algebraic geometry, motivic homotopy theory, and joint work on nilpotence and descent in equivariant stable homotopy theory.^[ref]