The Electric Universe
Plasma cosmology is a term describing a loose set of non-standard ideas about cosmology, some of which are attributed to the 1970 Nobel laureate Hannes Alfvén. Ionized gases, or plasmas, play a central part in plasma cosmology’s explanation for the development of the universe. Alfvén proposed the use of plasma scaling to describe cosmological phenomena by extrapolating the results of terrestrial and space plasma physics experiments to scales orders-of-magnitude greater, see box.
Some of the ideas of plasma cosmology contradict the current consensus of astrophysicists that Einstein’s theory of general relativity, a theory of gravity, explains the origin and evolution of the universe on cosmic scales, relying instead on the further development and application of classical mechanics and electrodynamics to astrophysical plasmas.
Joining of space plasma filaments
One of the most basic and important concepts in plasma cosmology is how plasma filaments combine together to enable them to carry the enormous currents required for plasma cosmology. Assuming an existing magnetic field and two plasma filaments, aligned along the magnetic field lines and each carrying an axial electric current opposite to the magnetic field (i.e. Birkeland currents), and for simplicity ignoring gravity. The currents in the two filaments will produce circular magnetic fields around them, which interact with the current in the other filament to generate a force attracting the two filaments together (use the right hand rule to determine the direction of the magnetic field, then Fleming’s left-hand rule to show each filament is attracted to the other, i.e. “like” currents attract). However, as the filaments move towards each other, the original (or background) external magnetic field and the motion interact to cause a current across the filaments (use Fleming’s right-hand rule, N.B. not the same as the “right hand rule” used before). The current is composed of protons moving in the direction of the current and electrons moving in the opposite sense. The electrons and protons that form this current will congregate at opposite sides of the filament. Using Fleming’s right-hand rule again, the filament motion interacts with the circular magnetic field surrounding the other filament, causing a secondary current to flow at the filament edges, in the opposite direction to the main current (not surprising, since originally we used Fleming’s left-hand rule for motors to determine the direction of motion, finally we used Fleming’s right-hand rule for generators, in the same field, to determine the direction of this secondary current).Since the electrons move much faster than the protons, the current profile across the filaments will be unbalanced, which means the attraction between the filaments is now offset from their centres. As the two filaments move towards and past each other, the excess charges on the inner faces of the filaments will repel each other as they are like charges. An equilibrium is reached between the repulsive force from the like charges on the inner surfaces of the filaments, and the attractive force from the main (like) currents. The two filaments become twisted together into a rotating double filament, which acts as if it were a single filament and can combine with another filament in the same way. Thus plasma filaments tend to “pinch” together, this being an example of a z-pinch since the current is in the z-direction with an azimuthal magnetic field. Magnetic fields can remove angular momentum, in the same way as stellar magnetic braking does, allowing the pinching to continue, unlike in the case of gravity alone where centrifugal force will eventually limit the contraction.
Interestingly, computer simulations in the 1980s showing the cross-section of two plasma filaments coalescing mimicked the shape of real galaxies, as had experiments done in the 1950s by Winston H. Bostick.
Galaxy formation, active galaxy nuclei and galaxy rotation curves
Supporting evidence for plasma cosmology comes from simulations of galaxy formation by A.L. Perrat. Simulations of colliding plasma clouds, starting 300,000 light years apart in filaments with currents of 1018 Amps, showed many similarities with observations of galaxies. This is a more complicated 3D version of two plasma filaments joining. Basically, the clouds begin to spin and are distorted (because of the same offset forces as in the case of the filaments joining) into two arms, separated at the centre by a buffer region (which corresponds to the gap between the filaments in the case of two filaments joining). The simulations also showed central radio sources of synchrotron radiation and emerging jets of material from the central buffer region, which looked like that observed from quasars and active galactic nuclei, without the need for supermassive black holes required in simulations based on gravity alone. Extending the simulation run time showed “the transition of double radio galaxies to radioquasars to radioquiet QSO’s to peculiar and Seyfert galaxies, finally ending in spiral galaxies”. The simulation accounted for the spin of galaxies (they gain spin at the expense of the magnetic fields), and also accounted for flat galaxy rotation curves without dark matter (the discrepancy between observed galaxy rotation curves and those simulated based on gravity alone had to be accounted for by introducing dark matter). With magnetic fields in play, the spiral arms of galaxies are like rolling springs that have the same rotational velocity along their length, creating in simulations flat galaxy rotation curves in spiral galaxies as observed in nature.
Complementing and in agreement with these simulation studies by Perrat was an analytical model of a plasma quasar mechanism by Lerner. This contradicts the standard model of quasars as being powered by supermassive black holes which are illuminated by radiation from the luminous matter they are accreting.
Experimentally plasma filaments are typically 10,000 times longer than they are wide. Thus to form galaxies, the filaments would be 100,000 light years across and one billion light years long, and such filaments would form the large-scale structure of the universe such as the Great Wall: 500 million light-years long, 300 million light-years wide and 15 million light-years thick. Prior to the discovery of the Great Wall in 1989 the mainstream consensus was that at these scales the universe would be uniform, but plasma cosmology had predicted the scale of these structures years before then.
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