Astrophysics (Index)About

alternative cosmologies

(non-standard cosmologies)
(cosmological models other than Big Bang/Lambda-CDM)

Alternative cosmologies (non-standard cosmologies) are cosmological models that differ from the standard cosmology (aka the concordance model), i.e., differ from the cosmological model currently accepted to the degree that it can be assumed. Before Hubble expansion was noticed and established as fact, it was generally assumed the universe merely remained through the ages much as viewed and this idea continued to be developed even after the widespread acceptance of the Hubble expansion, this non-expanding model eventually termed the steady state model, which could be called the standard cosmology of the past, but eventually became an alternative. It lost much of the ground it still held when the CMB was detected, and a model based on the Big Bang became accepted as the standard cosmology. This standard has since undergone modification, incorporating further theories inflation, dark energy, refined ideas about dark matter, and to match more recent observation, resulting in the Lambda-CDM model, the current standard cosmology. More recent cosmology ideas include theories that do not challenge Lambda-CDM but offer deeper explanation: many of these lack practical means of testing their validity. Also, recent proposed (non-cosmological) physics theories often have cosmological implications. Among them are refinements of the standard model of particle physics, and theories of gravity (alternatives or adjustments to general relativity). The latter have been motivated to explain the phenomenon that motivates the concepts of dark matter and dark energy, such as DGP gravity and MOND.

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