Determining representations from invariant dimensions.
Développement asymptotique du noyau de la chaleur hypoelliptique sur la diagonale
On obtient ici le développement asymptotique, en temps petit et sur la diagonale, du noyau de la chaleur associé à un opérateur dégénéré du second ordre satisfaisant à la condition forte d’hypoellipticité de Hörmander.
Differentiability from the representation formula and the Sobolev-Poincaré inequality
In the geometries of stratified groups, we provide differentiability theorems for both functions of bounded variation and Sobolev functions. Proofs are based on a systematic application of the Sobolev-Poincaré inequality and the so-called representation formula.
Differential operators of gradient type associated with spherical harmonics
Differential operators on equivariant vector bundles over symmetric spaces.
Differential Operators on Homogeneous Spaces. I. Irreducibility of the Associated Variety for Annihilators of Induced Modules.
Differential operators on homogeneous spaces. II : relative enveloping algebras
Dispersive and Strichartz estimates on H-type groups
Our purpose is to generalize the dispersive inequalities for the wave equation on the Heisenberg group, obtained in [1], to H-type groups. On those groups we get optimal time decay for solutions to the wave equation (decay as ) and the Schrödinger equation (decay as ), p being the dimension of the center of the group. As a corollary, we obtain the corresponding Strichartz inequalities for the wave equation, and, assuming that p > 1, for the Schrödinger equation.
Distribution de points sur une sphère
Distributions of Positive Type and Representations of Lie Groups.
Dunkl hyperbolic equations.