Higher-rank lattices actions on conformal structures
In this talk I will discuss both Lie groups and lattices actions by conformal transformation of a pseudo-Riemannian manifold, related to the Lorentzian Lichnerowicz' conjecture.
I will first discuss dynamics of $SL(2,\mathbb R)$-actions on closed Lorentzian manifolds, and then I will detail recent advances for higher-rank lattices conformal actions, and ongoing works with Thierry Barbot in the specific Lorentzian case.