3 papers
math.DG2007
A note on conformal connections on lightlike hypersurfaces
Cyriaque Atindogbe, Lionel Bérard Bergery
Degenerate submanifolds of pseudo-Riemannian manifolds are quite difficult to study because there is no prefered connection when the submanifold is not totally geodesic. For the pa…
math.DG2007
-tensors on lightlike hypersurfaces
Cyriaque Atindogbe, Lionel Bérard Bergery
This paper introduces $\anabla$-tensors on lightlike hypersurfaces of signature , and investigates on their properties in connection with the null geom…
math.RT2007
Representations admitting two pairs of supplementary invariant spaces
Lionel Bérard Bergery, Thomas Krantz
We examine the lattice generated by two pairs of supplementary vector subspaces of a finite-dimensional vector space by intersection and sum, with the aim of applying the results t…