Magnetohydrodynamics

Abstract

In this chapter we use statistical approaches to coronal plasmas, ‘smearing out’ individual particles to a fluid. Although their individuality is lost, the particles’ collective physical properties are retained. Magnetohydrodynamics (MHD) is a fluid theory. It is appropriate for coronal phenomena that take place on a relatively large scale and are slow. The main branches of MHD are: equilibria, waves, instabilities, and reconnection, on each of which there are already excellent books. These basic processes have been applied to dynamo theory, magneto-convection, flows in the photosphere and chromosphere, coronal loops, prominences, flares, coronal heating, and stellar winds, again on each of which whole books have been written.