‘ Big Bang ’

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"Big Bang" A hypothetical model of the universe which postulates that all matter and energy were once concentrated into an unimaginably dense state, or primaeval atom, from which it has been expanding since a creation event some 13-10 thousand million years ago. The main evidence favouring this model comes from cosmic background radiation and the redshifts of galaxies. Evidence of an expanding universe was announced by Edwin Hubble in 1929, and is now generally accepted. >> cosmology; Hubble; redshift; universe

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