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

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 نشر من قبل Pierfrancesco Di Cintio
 تاريخ النشر 2019
  مجال البحث فيزياء
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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 $Lambda_{rm max}$ decreases with $N$. The values of its inverse (the so-called Lyapunov time $t_lambda$) 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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