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arXiv · 1910.12881

The Null Geodesics of the Kerr Exterior

Samuel E. Gralla·Alexandru Lupsasca
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Abstract

The null geodesic equation in the Kerr spacetime can be expressed as a set of integral equations involving certain potentials. We classify the roots of these potentials and express the integrals in manifestly real Legendre elliptic form. We then solve the equations using Jacobi elliptic functions, providing the complete set of null geodesics of the Kerr exterior as explicit parameterized curves.

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Samuel E. Gralla, Alexandru Lupsasca. 2020-07-20. The Null Geodesics of the Kerr Exterior. https://doi.org/10.1103/physrevd.101.044032

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