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Parametrization of singularities of the Demiański-Newman spacetimes

J. Gariel·G. Marcilhacy·N. O. Santos·R. Colistete Jr
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Abstract

We propose a new presentation of the Demiański-Newman (DN) solution of the axisymmetric Einstein equations. We introduce new dimensionless parameters $p$, $q$ and $s$, but keeping the Boyer-Lindquist coordinate transformation used for the Kerr metric in the Ernst method. The family of DN metrics is studied and it is shown that the main role of $s$ is to determine the singularities, which we obtain by calculating the Riemann tensor components and the invariants of curvature. So, $s$ reveals itself as the parameter of the singular rings on the inner ergosphere.

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J. Gariel, G. Marcilhacy, N. O. Santos, R. Colistete Jr. 2000-12-01. Parametrization of singularities of the Demiański-Newman spacetimes. https://arxiv.org/abs/gr-qc/0012004

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