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arXiv · 2311.01863

Gravitational Waves Generated by Null Cosmic Strings

D. V. Fursaev·E. A. Davydov·I. G. Pirozhenko·V. A. Tainov
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Abstract

Null cosmic strings are shown to disturb gravitational fields of massive bodies and create outgoing gravitational waves (GW). Perturbations of the metric caused by a straight null string and a point-like massive source are found as solutions to linearized Einstein equations on a flat space-time. An analytic approximation for their asymptotic at future null infinity is derived. A space-time created by the source and the string is shown to have asymptotically polyhomogeneous form. We calculate GW flux in such space-times and demonstrate that the averaged intensity of the radiation is maximal in the direction of the string motion. Opportunities to detect null string generated gravity waves are briefly discussed.

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D. V. Fursaev, E. A. Davydov, I. G. Pirozhenko, V. A. Tainov. 2023-11-03. Gravitational Waves Generated by Null Cosmic Strings. https://arxiv.org/abs/2311.01863

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