Perturbative approach to numerical simulations of highly magnetised relativistic plasma

在高能天体物理学的许多现象中，我们处理的是极端磁化的等离子体，其中电磁能量密度超过等离子体的静止质能密度。到目前为止，这种等离子体的数值研究已经在1）相对论磁流体力学（RMHD）或2）无力电动力学（FFE）或3）直接粒子力学（PIC）的框架内进行。所有这些方法都有严重的局限性。特别是，RMHD方程是僵硬的制度下的考虑，FFE完全忽略等离子体惯性，PIC不允许处理大分离的微观和宏观尺度上遇到的天体物理系统。本计画旨在发展一个微扰的RMHD数值格式，其中等离子体惯性被视为小扰动。

In many phenomena of high-energy astrophysics we are dealing with extremely magnetised plasma where the electromagnetic energy density exceeds the rest mass-energy density of plasma. So far the numerical studies of such plasma have been carried out within the frameworks of either 1) Relativistic Magnetohydrodynamics (RMHD) or 2) Force-free electrodynamics (FFE) or 3) Direct particle mechanics (PIC). All these approaches have severe limitations. In particular, RMHD equations are stiff in the regime under the consideration, FFE ignores plasma inertial altogether, PIC does not allow to deal with the large separation of micro and macro scales encountered in the astrophysical systems. This project aims to develop a perturbative RMHD numerical scheme, where the plasma inertia is treated as small perturbation.