Here e is the elementary charge ( e > 0 ), c is the speed of light, m i is the mass of the ion, E ( r , t ) and B ( r , t ) represent collective self-consistent electromagnetic field created in the point r at time moment t by all plasma particles. The essential difference of this system of equations from equations for particles in an external electromagnetic field is that the self-consistent electromagnetic field depends in a complex way on the distribution functions of electrons and ions f e ( r , p , t ) and f i ( r , p , t ) .