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arXiv · 1907.12774

$N$-body chaos, phase-space transport and relaxation in numerical simulations

Pierfrancesco Di Cintio·Lapo Casetti
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Abstract

Using direct $N$-body simulations of self-gravitating systems we study the dependence of dynamical chaos on the system size $N$. We find that the $N$-body chaos quantified in terms of the largest Lyapunov exponent $Λ_{\rm max}$ decreases with $N$. The values of its inverse (the so-called Lyapunov time $t_λ$) are found to be smaller than the two-body collisional relaxation time but larger than the typical violent relaxation time, thus suggesting the existence of another collective time scale connected to many-body chaos.

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Pierfrancesco Di Cintio, Lapo Casetti. 2019-07-30. $N$-body chaos, phase-space transport and relaxation in numerical simulations. https://doi.org/10.1017/s1743921319006744

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