Nuts have no hair
arXiv:gr-qc/9508042 · doi:10.1088/0264-9381/12/12/004
Abstract
We show that the Riemannian Kerr solutions are the only Riemannian, Ricci-flat and asymptotically flat -metrics on a 4-dimensional complete manifold of topology which have (at least) a 1-parameter group of periodic isometries with only isolated fixed points ("nuts") and with orbits of bounded length at infinity.
8 pages, Latex file, no figures