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arXiv · 2009.08163

A numerical stability analysis for the Einstein-Vlasov system

Sebastian Günther·Jacob Körner·Timo Lebeda·Bastian Pötzl·Gerhard Rein·Christopher Straub·Jörg Weber
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Abstract

We investigate stability issues for steady states of the spherically symmetric Einstein-Vlasov system numerically in Schwarzschild, maximal areal, and Eddington-Finkelstein coordinates. Across all coordinate systems we confirm the conjecture that the first binding energy maximum along a one-parameter family of steady states signals the onset of instability. Beyond this maximum perturbed solutions either collapse to a black hole, form heteroclinic orbits, or eventually fully disperse. Contrary to earlier research, we find that a negative binding energy does not necessarily correspond to fully dispersing solutions. We also comment on the so-called turning point principle from the viewpoint of our numerical results. The physical reliability of the latter is strengthened by obtaining consistent results in the three different coordinate systems and by the systematic use of dynamically accessible perturbations.

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Sebastian Günther, Jacob Körner, Timo Lebeda, Bastian Pötzl, Gerhard Rein, Christopher Straub, Jörg Weber. 2020-09-17. A numerical stability analysis for the Einstein-Vlasov system. https://doi.org/10.1088/1361-6382/abcbdf

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