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A new geometric invariant on initial data for Einstein equations

Sergio Dain
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Abstract

For a given asymptotically flat initial data set for Einstein equations a new geometric invariant is constructed. This invariant measure the departure of the data set from the stationary regime, it vanishes if and only if the data is stationary. In vacuum, it can be interpreted as a measure of the total amount of radiation contained in the data.

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Sergio Dain. 2004-12-01. A new geometric invariant on initial data for Einstein equations. https://doi.org/10.1103/physrevlett.93.231101

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