ABSTRACT
A boundary is an interface that separates the different regions of space. A plasma boundary is defined through discontinuous fluid parameters such as density and temperature in the same way ordinary fluid boundaries are defined. However, plasmas are coupled to electric and magnetic fields, and therefore the requirements must also include the behavior of discontinuous electromagnetic fields. The complete set of discontinuous variables in collisionless plasma fluids includes the mass density ρ m, flow velocity U, pressure tensor p, current J, and the magnetic and electric fields B and E.
