Magnetohydrodynamic Equations in a Gravitational Field and Excitation of Magnetohydrodynamic Shock Waves by a Gravitational Wave

TL;DR

This paper derives relativistic magnetohydrodynamic equations in gravitational fields and demonstrates how gravitational waves can generate shock waves in magnetized plasma, with implications for astrophysical phenomena.

Contribution

It provides exact solutions for plasma motion in gravitational fields and reveals how gravitational waves can induce shock waves in strong magnetic fields.

Findings

Small amplitude gravitational waves can generate shock MHD waves.

Shock waves propagate at subluminal velocities.

Astrophysical plasma acceleration effects are discussed.

Abstract

On the basis of simple principles we derive and investigate the equations of relativistic plasma magnetohydrodynamics (MHD) in an arbitrary gravitational field. An exact solution describing the motion of magnetoactive plasma against the background of the metric of a plane gravitational wave (PGW) with an arbitrary amplitude is obtained. It is shown that in strong magnetic fields even a sufficiently small amplitude PGW can create a shock MHD wave, propagating at a subluminal velocity. Astrophysical consequences of the anomalous plasma acceleration are considered.