big bang theory

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big bang theory The current explanation for the origin of the universe, in which it expands and evolves from an initial very high-temperature condition about 15–20 billion years ago. The expansion time is given from the reciprocal of the Hubble constant (the rate at which galaxies are receding). All all-pervasive background radiation of 3K is considered to be residual from the big bang and is the strongest supporting evidence for the theory.

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