How to Measure Deviation from the Kerr Initial Data: Recent Progress

  • Thomas BäckdahlEmail author
  • Juan A. Valiente Kroon
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 157)


In these proceedings we will present recent progress concerning a construction of a geometric invariant for initial data sets for the Einstein vacuum field equations. This geometric invariant vanishes if and only if the initial data set corresponds to data for the Kerr spacetime, and thus, it characterizes this type of data. The construction was initially based on Killing spinors, but here we translate the results to tensor language. We can now handle both compact domains and domains reaching the asymptotically flat ends.



T.B. is funded by the Max-Planck-Institute for Gravitational Physics, Albert Einstein Institut.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Max Planck Institut für GravitationsphysikAlbert Einstein InstitutGolmGermany
  2. 2.School of Mathematical SciencesQueen Mary University of LondonLondonUK

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