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arXiv · 1905.12905

Memory Effect and BMS-like Symmetries for Impulsive Gravitational Waves

Srijit Bhattacharjee·Arpan Bhattacharyya·Shailesh Kumar
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Abstract

Cataclysmic astrophysical phenomena can produce impulsive gravitational waves that can possibly be detected by the advanced versions of present-day detectors in the future. Gluing of two spacetimes across a null surface produces impulsive gravitational waves (in the phraseology of Penrose [1]) having a Dirac Delta function type pulse profile along the surface. It is known that BMS-like symmetries appear as soldering freedom while we glue two spacetimes along a null surface. In this note, we study the effect of such impulsive gravitational waves on test particles (detectors) or geodesics. We show explicitly some measurable effects that depend on BMS-transformation parameters on timelike and null geodesics. BMS-like symmetry parameters carried by the gravitational wave leave some "memory" on test geodesics upon passing through them.

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Srijit Bhattacharjee, Arpan Bhattacharyya, Shailesh Kumar. 2019-05-30. Memory Effect and BMS-like Symmetries for Impulsive Gravitational Waves. https://doi.org/10.1103/physrevd.100.084010

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