高导电流体在重力作用下运动时的磁场行为--一种新的理论相对论方法
How the magnetic field behaves during the motion of a highly conducting fluid under its own gravity--A new theoretical, relativistic approach
摘要：
在广义相对论的范围内，我们以完全协变的方式研究所谓的欧拉-麦克斯韦方程组。特别是，在理想的磁流体动力学极限分解成1的时间和1 + 2的空间分量的上述系统，我们把它在一个简化的形式，有利于物理洞察力的自引力，磁化流体的问题。中心的兴趣是法拉第方程的分解，导致一个新的一般解决方案，在运动的高导电流体的磁场的演变。根据后一关系式，磁场通常与标度因子的立方反比定律成比例地增长或衰减--分别与流体体积的连续收缩或膨胀相关联。磁场的变化规律，这对整个流体的运动有显着的影响，随后被应用到均匀（各向异性磁化）宇宙模型-特别是比安奇我的情况下-以及均匀和各向异性的引力坍缩在磁化环境中的研究。在宇宙学应用方面，我们导出了大尺度磁场作用下Bianchi I时空的演化方程（这些方程在小/大尺度极限下约化为FRW方程）。此外，新的磁场演化公式与标准的宇宙核合成约束的兼容性进行了检查。至于在天体物理中的应用，我们的结果预言，当沿磁力线的电Weyl张量（与潮汐力有关）超过磁能密度时，均匀引力坍缩将受到阻碍.最后，我们的模型表明，上述标准的满足最终被驱动到一个初始条件的问题。
英文摘要：
Within the context of general relativity we study in a fully covariant way the so-called Euler-Maxwell system of equations. In particular, on decomposing the aforementioned system into its 1 temporal and 1 + 2 spatial components at the ideal magnetohydrodynamic limit, we bring it in a simplified form that favors physical insight to the problem of a self-gravitating, magnetized fluid. Of central interest is the decomposition of Faraday's equation which leads to a new general solution governing the evolution of the magnetic field during the motion of the highly conducting fluid. According to the latter relation, the magnetic field generally grows or decays in proportion to the inverse cube law of the scale factor--associated with the continuous contraction or expansion of the fluid's volume respectively. The magnetic field's law of variation, which has remarkable implications for the motion of the whole fluid, is subsequently applied to homogeneous (anisotropic-magnetized) cosmological models--especially to the Bianchi I case--as well as to the study of homogeneous and anisotropic gravitational collapse in a magnetized environment. Concerning the cosmological application, we derive the evolution equations of Bianchi I spacetime permeated by large-scale magnetic fields (these equations reduce to their FRW counterparts at the small/large--scale limit). Also, the compatibility of the new evolution formula for the magnetic field with the standard cosmic nucleosynthesis constraint is examined. As for the application in astrophysics, our results predict that homogeneous gravitational implosion is impeded when the electric Weyl tensor (associated with tidal forces) along the magnetic forcelines overwhelms the magnetic energy density. Lastly, our model denotes that the satisfaction of the aforementioned criterion is ultimately driven into a problem of initial conditions.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
