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arXiv · 2409.03722

Kerr Geodesics in horizon-penetrating Kerr coordinates: description in terms of Weierstrass functions

Zuzanna Bakun·Angelika Łukanty·Anastasiia Untilova·Adam Cieślik·Patryk Mach
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Abstract

We revisit the theory of timelike and null geodesics in the (extended) Kerr spacetime. This work is a sequel to a recent paper by Cie\'{s}lik, Hackmann, and Mach, who applied the so-called Biermann-Weierstrass formula to integrate Kerr geodesic equations expressed in Boyer-Lindquist coordinates. We show that a formulation based on the Biermann-Weierstrass theorem can also be applied in horizon-penetrating Kerr coordinates, resulting in solutions that are smooth across Kerr horizons. Horizon-penetrating Kerr coordinates allow for an explicit continuation of timelike and null geodesics between appropriate regions of the maximal analytic extension of the Kerr spacetime. A part of this work is devoted to a graphic visualisation of such geodesics.

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Zuzanna Bakun, Angelika Łukanty, Anastasiia Untilova, Adam Cieślik, Patryk Mach. 2024-09-05. Kerr Geodesics in horizon-penetrating Kerr coordinates: description in terms of Weierstrass functions. https://arxiv.org/abs/2409.03722

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