A remark on the rigidity of conformally compact Poincar{é}-Einstein manifolds
arXiv:1803.03162 · doi:10.1007/s11005-018-01146-8
Abstract
In this paper, we give an optimal inequality relating the relative Yamabe invariant of a certain compactification of a conformally compact Poin-car{é}-Einstein manifold with the Yamabe invariant of its boundary at infinity. As an application, we obtain an elementary proof of the rigidity of the hyper-bolic space as the only conformally compact Poincar{é}-Einstein manifold with the round sphere as its conformal infinity.