Consider 1D Vlasov-poisson system with a fixed ion background and periodic condition on the space variable. First, we show that for general homogeneous equilibria, within any small neighborhood in the Sobolev space W^{s,p} (p>1,s<1+(1/p)) of the steady distribution function, there exist nontrivial travelling wave solutions (BGK waves) with arbitrary minimal period and traveling speed. This implies that nonlinear Landau damping is not true in W^{s,p}(s<1+(1/p)) space for any homogeneous equilibria and any spatial period. Indeed, in W^{s,p} (s<1+(1/p)) neighborhood of any homogeneous state, the long time dynamics is very rich, including travelling BGK waves, unstable homogeneous states and their possible invariant manifolds. Second, it is shown that for homogeneous equilibria satisfying Penrose's linear stability condition, there exist no nontrivial travelling BGK waves and unstable homogeneous states in some W^{s,p} (p>1,s>1+(1/p)) neighborhood. Furthermore, when p=2,we prove that there exist no nontrivial invariant structures in the H^{s} (s>(3/2)) neighborhood of stable homogeneous states. These results suggest the long time dynamics in the W^{s,p} (s>1+(1/p)) and particularly, in the H^{s} (s>(3/2)) neighborhoods of a stable homogeneous state might be relatively simple. We also demonstrate that linear damping holds for initial perturbations in very rough spaces, for linearly stable homogeneous state. This suggests that the contrasting dynamics in W^{s,p} spaces with the critical power s=1+(1/p) is a trully nonlinear phenomena which can not be traced back to the linear level.
Asymptotic stability of Bernstein-Greene-Kruskal (BGK) waves, Landau Damping, and scattering theory
Departamento de Física Matemática（数学物理系）；Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas（应用数学与系统研究所）；Universidad Nacional Autónoma de México（墨西哥国立自治大学）
Incompressible Navier-Stokes limit of non-bilinear kinetic equations and application to the BGK, nonlinear Fokker-Planck and Boltzmann-Fermi-Dirac equations
Nonlinear Landau damping for the two-species screened Vlasov-Poisson system with large initial distributions
State Key Laboratory of Mathematical Sciences and Institute of Applied Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences（中国科学院数学与系统科学研究院应用数学研究所）；School of Mathematical Sciences, University of Chinese Academy of Sciences（中国科学院大学数学科学学院）；Research Center of Nonlinear Science, School of Mathematics and Statistics, Wuhan Textile University（武汉纺织大学数学与统计学院非线性科学研究中心）；School of Mathematics and Computational Science, Xiangtan University & National Center for Applied Mathematics in Hunan（湘潭大学数学与计算科学学院 & 湖南应用数学中心）；Institute of Applied Mathematics, AMSS, CAS（中国科学院数学与系统科学研究院应用数学研究所）
A study of Landau damping with random initial inputs
对于具有随机不确定初值的泊松方程，证明了确定性方程（Caglioti and Maffei，{ \it J. Stat. Phys.}，92：301-323，1998）在类似于确定性情况的平滑性和小性假设下，如果时间渐近分布平滑地依赖于随机变量，则该时间渐近分布平滑地依赖于随机变量。其主要思想是将确定性收缩参数推广到更复杂的函数空间，以估计空间，速度和随机变量中的导数。这一结果表明，即使在时间可逆的非线性动力学方程中，随机空间规律性也能长时间保持。
Quantum Landau Damping with Coulomb Repulsion in the Whole Space
Academy of Mathematics and Systems Science, Chinese Academy of Sciences（中国科学院数学与系统科学研究院）；Unité de Mathématiques Pures et Appliquées CNRS and École Normale Supérieure de Lyon（法国国家科学研究中心与里昂高等师范学院纯与应用数学联合实验室）
