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Evidence for the Big Bang

Physics · Class 12

Evidence for the Big Bang consists of observations that support the model of an expanding universe that evolved from a hot, dense early state.

v=H₀d
2.7 K
T_CMB≈2.7K
Expansion of the Universe: Three major lines of evidence are: Distant galaxies show cosmological redshift. Hubble's relation:
Cosmic Microwave Background: The universe contains nearly uniform microwave radiation coming from all directions. It has an almo
Several independent observations support hot Big Bang cosmology.

Free-body idea — Evidence for the Big Bang — original sketch for this lesson (not copied from a textbook).