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Scattering of a Long Cosmic String by a Rotating Black Hole

Martin Snajdr·Valeri Frolov·Jean-Pierre DeVilliers
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Abstract

The scattering of a straight, infinitely long string by a rotating black hole is considered. We assume that a string is moving with velocity v and that initially the string is parallel to the axis of rotation of the black hole. We demonstrate that as a result of scattering, the string is displaced in the direction perpendicular to the velocity by an amount kappa(v,b), where b is the impact parameter. The late-time solution is represented by a kink and anti-kink, propagating in opposite directions at the speed of light, and leaving behind them the string in a new ``phase''. We present the results of the numerical study of the string scattering and their comparison with the weak-field approximation, valid where the impact parameter is large, b/M >> 1, and also with the scattering by a non-rotating black hole which was studied in earlier works.

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Martin Snajdr, Valeri Frolov, Jean-Pierre DeVilliers. 2002-11-03. Scattering of a Long Cosmic String by a Rotating Black Hole. https://doi.org/10.1088/0264-9381%2F19%2F23%2F308

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