and J
are functions of E
and B
. The expression
of J
as a function of E
is called the constitutive relation. For linearized fields, this
relation can be expressed in general as
Maxwell equations (??) are a closed system only if the charge and the current densities are
known. In a plasma ρ and J are functions of E and B. The expression
of J as a function of E is called the constitutive relation. For linearized fields, this
relation can be expressed in general as
 | (3) |
where S
is the conductivity tensor, which depends upon the plasma equilibrium.