Special Relativistic Magnetohydrodynamics with Gravitation
  We present a fully nonlinear and exact perturbation formulation of Einstein's
gravity with a general fluid and the ideal magnetohydrodynamics (MHD) without
imposing the slicing (temporal gauge) condition. Using this formulation, we
derive equations of special relativistic (SR) MHD in the presence of weak
gravitation. The equations are consistently derived in the limit of weak
gravity and action-at-a-distance in the maximal slicing. We show that in this
approximation the relativistic nature of gravity does not affect the SR MHD
dynamics, but SR effects manifest themselves in the metric, and thus
gravitational lensing. Neglecting these SR effects may lead to an
overestimation of lensing masses.
