Non-standard cosmology
A non-standard cosmology is a cosmological theory that contradicts the standard model of cosmology. The term has been used since the late-1960's after the discovery of the cosmic background radiation (CMR) in 1965 removed the steady state theory as a viable alternative to the big bang theory. Since around the time of the discovery of the CMR, this has in practice primarily meant any cosmological theory which argues that the big bang theory is "based on the wrong assumptions".
Standard model
The standard model of cosmology has asserted that:
- redshifts observed in distant galaxies are due to the expansion of the universe
- this expansion is due to the expansion of space-time as predicted by general relativity and that if you move backward in time you will eventually reach the big bang.
Non-standard cosmologies challenge one or both of these beliefs, usually asserting that one or the other of these beliefs are incorrect.
Alternatives
Alternative models of cosmology that do not challenge these two assertions are not termed non-standard cosmologies, even if they are not widely accepted. For example, the modified Newtonian dynamics is not a non-standard cosmology even though it radically challenges mainstream views on gravity
Non-standard
Besides the background cosmic radiation, the basic observation which a non-standard cosmology needs to deal with is the observation of cosmic redshift (ie., the apparent expansion of the universe). Halton Arp argues, in Quasar, Redshifts and Controversies, that Hubble's law can be invalidated. He has showsn that galaxies can exhibit strange redshifts, and that redshifts themselves could be quantized - something that current theories cannot explain at macroscopic scales.
In some non-standard cosmology this is not regarded as a general expansion of space time, but rather as result of physical effects of ambiplasma (explainable via concepts in the Sunyaev Zeldovic Effect). Also, some non-standard cosmology may attribute the redshift to physical effects of photons or it may assert that the universe is expanding but that this expansion is not the result of space's expansion itself (i.e. the Alfven universe, see Plasma cosmology).
See also
Main: Ekpyrotic, Plasma cosmology, Reciprocal System of Theory, Steady state theory
Creation: Creative evolution, Creation myths, Creationism