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arXiv · 1808.04886

Geodesic congruences, impulsive gravitational waves and gravitational memory

Martin O'Loughlin·Hovhannes Demirchian
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Abstract

In this paper we introduce a new approach to the study of the effects that an impulsive wave, containing a mixture of material sources and gravitational waves, has on a geodesic congruence that traverses it. We find that the effect of the wave on the congruence is a discontinuity in the B-tensor of the congruence. Our results thus provide a detector independent and covariant characterization of gravitational memory.

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Martin O'Loughlin, Hovhannes Demirchian. 2018-08-14. Geodesic congruences, impulsive gravitational waves and gravitational memory. https://doi.org/10.1103/physrevd.99.024031

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