Plasma cosmology Is a theory developed by Hannes Alfven in the 1960s. The theory says that,the intergalactic medium; that is the medium between the galaxies is a plasma!
Plasma,an ionised stage of gas,in which electrons are free and separated,from their parent positive nuclei.
The theory also claims that the extended galaxy curves,of the spiral galaxies,which is explained by the concept of Dark Matter right now,is actually due to electromagnetism. Electro magnetism at a large scale,universally.
The theory says that,electromagnetism in a large scale dominates gravity. Gravity is what the candidate of Big Bang theory,which is here localised to bring forth electromagnetism more globally than it.
Though Plasma cosmology haven’t yet be able to explain other evidences which supports Dark matter,it isn’t a bad theory in cosmology.
Plasma cosmology also explains the condition of temperature and Near Isotropy of the cosmic microwave background (CMB) radiation. But it can’t explain the Power spectrum seen in CMB,which is explainable by big bang theory,which is the most big drawback of plasma cosmology.