Space-time estimates of the 3D bipolar compressible Navier-Stokes-Poisson system with unequal viscosities  

作　　者：Zhigang Wu Weike Wang 

机构地区：[1]Department of Mathematics,Donghua University,Shanghai 201620,China [2]School of Mathematical Sciences,Shanghai Jiao Tong University,Shanghai 200240,China [3]Shanghai Frontier Science Center of Modern Analysis(CMA-Shanghai),Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Science China Mathematics》2024年第5期1059-1084,共26页中国科学（数学）（英文版）

基　　金：supported by National Natural Science Foundation of China(Grant No.11971100);supported by National Natural Science Foundation of China(Grant Nos.12271357,12161141004,and 11831011);Natural Science Foundation of Shanghai(Grant No.22ZR1402300);Shanghai Science and Technology Innovation Action Plan(Grant No.21JC1403600)。

摘　　要：The space-time behavior for the Cauchy problem of the 3D compressible bipolar Navier-Stokes-Poisson(BNSP)system with unequal viscosities is given.The space-time estimate of the electric field▽φ=▽(-△)^(-1)(n-Zρ)is the most important in deducing generalized Huygens’principle for the BNSP system and it requires proving that the space-time estimate of n-Zρonly contains the diffusion wave due to the singularity of the operator▽(-△)^(-1).A suitable linear combination of unknowns reformulating the original system into two small subsystems for the special case(with equal viscosities)in Wu and Wang(2017)is crucial for both linear analysis and nonlinear estimates,especially for the space-time estimate of▽φ.However,the benefits from this reformulation will no longer exist in general cases.Here,we study an 8×8 Green’s matrix directly.More importantly,each entry in Green’s matrix contains wave operators in the low-frequency part,which will generally produce Huygens’wave;as a result,one cannot achieve the space-time estimate of n-Zρthat only contains the diffusion wave as before.We overcome this difficulty by taking a more detailed spectral analysis and developing new estimates arising from subtle cancellations in Green’s function.

关 键 词：Green's function bipolar Navier-Stokes-Poisson system unequal viscosities 

分 类 号：O53[理学—等离子体物理] O175[理学—物理]