Representations of groups on eigenspaces of invariant differential operators
Résolubilité sur un espace riemannien symétrique
Riesz means for the eigenfunction expansions for a class of hypo-elliptic differential operators
We study the Riesz means for the eigenfunction expansions of a class of hypoelliptic differential operators on the Heisenberg group. The operators we consider are homogeneous with respect to dilations and invariant under the action of the unitary group. We obtain convergence results in norm, at Lebesgue points and almost everywhere. We also prove localization results.
Rochlin invariants, theta functions and the holonomy of some determinant line bundles.