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arXiv · gr-qc/9508042

Nuts have no hair

Walter Simon
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Abstract

We show that the Riemannian Kerr solutions are the only Riemannian, Ricci-flat and asymptotically flat ${\rm C}^{2}$-metrics $g_{μν}$ on a 4-dimensional complete manifold ${\cal M}$ of topology ${\rm R}^{2} \times {\rm S}^{2}$ 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.

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Walter Simon. 1995-08-18. Nuts have no hair. https://doi.org/10.1088/0264-9381%2F12%2F12%2F004

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