Chaotic motion in the Johannsen-Psaltis spacetime

0484970 - ASÚ 2018 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Zelenka, Ondřej - Lukes-Gerakopoulos, Georgios
Chaotic motion in the Johannsen-Psaltis spacetime.
Proceedings of RAGtime 17/19: Workshops on black holes and neutron stars. Opava: Silesian University, 2017, s. 253-260. Publications of the Institute of Physics, 8. ISBN 9788075102577. ISSN 2336-5668.
[RAGtime /17.-19./. Opava (CZ), 17.11.2015-19.11.2015]
Grant CEP: GA ČR(CZ) GJ17-06962Y
Institucionální podpora: RVO:67985815
Klíčová slova: chaos * geodesic motion * black holes
Obor OECD: Astronomy (including astrophysics,space science)
http://proceedings.physics.cz/images/proc17/zel.pdf

The Johannsen-Psaltis spacetime is a perturbation of the Kerr spacetime designed to avoid pathologies like naked singularities and closed timelike curves. This spacetime depends not only on the mass and the spin of the compact object, but also on extra parameters, making the spacetime deviate from Kerr. In this work we consider only the lowest order physically meaningful extra parameter. We use numerical examples to show that geodesic motion in this spacetime can exhibit chaotic behavior. We study the corresponding phase space by using Poincaré sections and rotation numbers to show chaotic behavior, and we use Lyapunov exponents to directly estimate the sensitivity to initial conditions for chaotic orbits.
Trvalý link: http://hdl.handle.net/11104/0280092