The Universe

Origin of the Universe

How did the universe begin?

The scientific theory that describes the origin of the universe is called the Big Bang. According to the Big Bang theory, the universe began to exist as a single point of spacetime, and it has been expanding ever since. As that expansion has occurred, the conditions in the universe have changed—from small to big, from hot to cold, and from young to old—resulting in the universe we observe today.


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