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On the Existence of Radiation Gauges in Petrov type II spacetimes

Larry R. Price·Karthik Shankar·Bernard F. Whiting
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Abstract

The radiation gauges used by Chrzanowski (his IRG/ORG) for metric reconstruction in the Kerr spacetime seem to be over-specified. Their specification consists of five conditions: four, which we treat here as valid gauge conditions, plus an additional condition on the trace of the metric perturbation. In this work, we utilize a newly developed form of the perturbed Einstein equations to establish a condition -- on a particular tetrad component of the stress-energy tensor -- under which the full IRG/ORG can be imposed. Using gauge freedom, we are able to impose the full IRG for Petrov type II and type D backgrounds, using a different tetrad for each case. As a specific example, we work through the process of imposing the IRG in a Schwarzschild background, using a more traditional approach. Implications for metric reconstruction using the Teukolsky curvature perturbations in type D spacetimes are briefly discussed.

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Larry R. Price, Karthik Shankar, Bernard F. Whiting. 2007-04-18. On the Existence of Radiation Gauges in Petrov type II spacetimes. https://doi.org/10.1088/0264-9381%2F24%2F9%2F014

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