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Vlasov equation and $N$-body dynamics - How central is particle dynamics to our understanding of plasmas?

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 نشر من قبل Yves Elskens
 تاريخ النشر 2014
  مجال البحث فيزياء
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 تأليف Yves Elskens




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Difficulties in founding microscopically the Vlasov equation for Coulomb-interacting particles are recalled for both the statistical approach (BBGKY hierarchy and Liouville equation on phase space) and the dynamical approach (single empirical measure on one-particle $(mathbf{r},mathbf{v})$-space). The role of particle trajectories (characteristics) in the analysis of the partial differential Vlasov--Poisson system is stressed. Starting from many-body dynamics, a direct derivation of both Debye shielding and collective behaviour is sketched.

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