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arXiv · 1701.05434

Dain's invariant on non-time symmetric initial data sets

Juan A. Valiente Kroon·Jarrod L. Williams
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Abstract

We extend Dain's construction of a geometric invariant characterising static initial data sets for the vacuum Einstein field equations to situations with a non-vanishing extrinsic curvature. This invariant gives a measure of how much the initial data sets deviates from stationarity. In particular, it vanishes if and only if the initial data set is stationary. Thus, the invariant provides a quantification of the amount of gravitational radiation contained in the initial data set.

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Juan A. Valiente Kroon, Jarrod L. Williams. 2017-05-12. Dain's invariant on non-time symmetric initial data sets. https://doi.org/10.1088/1361-6382%2Faa7102

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