Plasma Cosmology

Plasma cosmology is a term describing a loose set of non-standard ideas about cosmology. Its central idea is that the dynamics of ionized gases (or plasmas) plays a decisive role in the physics of the universe at scales larger than the Solar system. Today, almost all cosmologists and astronomers are dismissive of the idea. The current consensus of astrophysicists is instead that Einstein's theory of general relativity, a theory of gravity, explains the structure and evolution of the universe on cosmic scales after the cosmic microwave background radiation decoupled from matter.

Some of the ideas of plasma cosmology are attributed to the 1970 Nobel laureate Hannes Alfvén, although they can be traced back at least as early as the ideas of George Woodward Warder and Kristian Birkeland around the beginning of the 20th century. Alfvén proposed the use of plasma scaling to extrapolate the results of laboratory experiments and space plasma physics observations to scales orders-of-magnitude greater (see box). While it is widely agreed that plasma physics is essential to many astrophysical phenomena in the early universe and is still important today to phenomena up to the scale of the Solar system, plasma cosmology continues this extrapolation to the universe on the largest observable scales.

The term plasma universe is sometimes used as a synonym for plasma cosmology and sometimes plasma cosmology is seen as the evolution of the plasma universe.