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arXiv · 1002.4378

An Extended Kerr-Schild Ansatz

Benjamin Ett·David Kastor
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Abstract

We present an analysis of the vacuum Einstein equations for a recently proposed extension of the Kerr-Schild ansatz that includes a spacelike vector field as well as the usual Kerr-Schild null vector. We show that many, although not all, of the simplifications that occur in the Kerr-Schild case continue to hold for the extended ansatz. In particular, we find a simple set of sufficient conditions on the vectors such that the vacuum field equations truncate beyond quadratic order in an expansion around a general vacuum background solution. We extend our analysis to the electrovac case with a related ansatz for the gauge field.

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Benjamin Ett, David Kastor. 2010-06-20. An Extended Kerr-Schild Ansatz. https://doi.org/10.1088/0264-9381%2F27%2F18%2F185024

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