2021/07/09 by Böhm, Christoph, Lafuente, Ramiro A. · 5 citations
#14L24 #53C25 #53C30 #57S20 #Differential Geometry (math.DG) #FOS: Mathematics
paper · doi:10.48550/arxiv.2107.04210
For Einstein manifolds with negative scalar curvature admitting an isometric action of a Lie group G with compact, smooth orbit space, we show the following rigidity result: The nilradical N of G acts polarly, and the N-orbits can be extended to minimal Einstein submanifolds. As an application, we prove the Alekseevskii conjecture: Any homogeneous Einstein manifold with negative scalar curvature is diffeomorphic to a Euclidean space.