Conformal Actions of Nilpotent Groups on Pseudo-riemannian Manifolds Charles Frances and Karin Melnick
نویسنده
چکیده
A basic question, first addressed by A. Lichnerowicz, is to characterize the pseudo-Riemannian manifolds (M,σ) for which Conf M does not preserve any metric in [σ]; in this case, Conf M is essential. The Lichnerowicz conjecture, proved by J. Lelong-Ferrand [LF1], says, for (M,σ) a Riemannian manifold of dimension ≥ 2, if Conf M is essential, then M is conformally equivalent to the round sphere or Euclidean space.
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تاریخ انتشار 2008