Origin of cosmic magnetic-fields

• A summary is given of the reasons why an understanding of cosmic hydromagnetic phenomena is impossible without describing them explicitly by electric currents. This applies also to the production of cosmic magnetic fields. The purpose of the paper is to demonstrate that a simple translation from the traditional magnetic field description to a current description gives important new aspects of cosmical electrodynamics, including a new approach to the production of magnetic fields.One of the results is that the kink-instability of electric currents is found to be the basic physical phenomenon responsible for magnetic flux generation in cosmical physics. Laboratory plasma experiments demonstrate the existence of a simple mechanism for flux amplification, and it seems obvious that the same mechanism should work also under cosmical conditions.A simple model is discussed. We start from a poloidal magnetic field (which may be extremely weak). Differential motions change the field configuration which means that kinetic energy is transferred into magnetic energy of induced toroidal fields. The currents associated with these get unstable when the toroidal energy exceeds the poloidal energy resulting in an amplification of the original poloidal field.This simple process of transfer of kinetic energy into poloidal magnetic energy is probably the main mechanism for magnetic flux generation in low density cosmic plasmas. In view of the serious difficulties of planetary dynamo theories, attempts should be made to develop it into a theory of the magnetization of celestial bodies.

Ämnesord

NATURVETENSKAP  -- Fysik -- Astronomi, astrofysik och kosmologi (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Astronomy, Astrophysics and Cosmology (hsv//eng)

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)