The Big Bang Theory explains the origin and expansion of the universe 13.7 billion years ago.
The Big Bang Theory is the prevailing cosmological model explaining the origin and expansion of the universe. According to this theory, the universe began about 13.7 billion years ago from a hot, dense state and has been expanding ever since.
This theory is supported by evidence like the cosmic microwave background radiation and the isotropic expansion of the universe. It posits that all matter, energy, space, and time originated from a single point during the Big Bang.
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