Optimal Decay Rates for the Highest-Order Derivatives of Solutions for the Compressible MHD Equations with Coulomb Force

Abstract

For the Cauchy problem of the 3D compressible MHD equations with Coulomb force, the large time behavior of this model is further investigated in this article. Compared to the previous related works in Tan-Tong-Wang [J. Math. Anal. Appl. 427 (2015) 600–617], the main novelty of this paper is that we prove the optimal decay rates for the highest-order spatial derivatives of the solutions to the compressible MHD equations with Coulomb force, which are the same as those of the heat equation.