Abstract In this paper the repulsive effects in the Kerr and Kerr--Newman fields are
discussed. The contributions made by all parameters of the fields and test
particles to the repulsive effects are also discussed, and the accretive
effect on interstellar dust, i.e. the distribution of dust is calculated.
The discussion is also carried out on the slow rotation of the Kerr field in
which the effect is related to the positions and velocities of the particles
and the orientations of their trajectories as well.
Received: 02 January 2006
Revised: 19 February 2006
Published: 20 May 2006