Les personnes qui possèdent un compte PLM-Mathrice sont invitées à l'utiliser.
GT Rencontres d'Analyse

# Topology of the Heisenberg group and H=W questions (I)

## by Armin Shikorra (Universität Freiburg)

mardi 4 octobre 2016 de au (Europe/Paris)
at Université Catholique de Louvain ( Auditoire CYCL08, bâtiment Marc de Hemptinne )
Louvain-la-Neuve Belgique
 Description Approximation of Sobolev maps into Riemannian manifolds by smooth functions depends on the topology of the manifold. We report on recent progress of density questions for Sobolev maps into the Heisenberg group and related topological problems. The Heisenberg groups are examples of sub-Riemannian manifolds homeomorphic, but not diffeomorphic to the Euclidean space. Their metric is derived from curves which are only allowed to move in so-called horizontal directions.