Consider the Vlasov-Poisson-Landau system with Coulomb potential in the
    weakly collisional regime on a $3$-torus, i.e. $$\begin{aligned} \partial_t
    F(t,x,v) + v_i \partial_{x_i} F(t,x,v) + E_i(t,x) \partial_{v_i} F(t,x,v) = \nu
    Q(F,F)(t,x,v),\\ E(t,x) = \nabla \Delta^{-1} (\int_{\mathbb R^3} F(t,x,v)\,
    \mathrm{d} v – \frac{1}{(2\pi)^3}\int_{\mathbb T^3} \int_{\mathbb R^3}
    F(t,x,v)\, \mathrm{d} v \, \mathrm{d} x), \end{aligned}$$ with $\nu\ll 1$. We
    prove that for $\epsilon>0$ sufficiently small (but independent of $\nu$),
    initial data which are $O(\epsilon \nu^{1/3})$-Sobolev space perturbations from
    the global Maxwellians lead to global-in-time solutions which converge to the
    global Maxwellians as $t\to \infty$. The solutions exhibit uniform-in-$\nu$
    Landau damping and enhanced dissipation.

    Our main result is analogous to an earlier result of Bedrossian for the
    Vlasov-Poisson-Fokker-Planck equation with the same threshold. However, unlike
    in the Fokker-Planck case, the linear operator cannot be inverted explicitly
    due to the complexity of the Landau collision operator. For this reason, we
    develop an energy-based framework, which combines Guo’s weighted energy method
    with the hypocoercive energy method and the commuting vector field method. The
    proof also relies on pointwise resolvent estimates for the linearized density

    Source link


    Leave A Reply