Question

explain THE BIG BANG THEORY in very simple words

Answer 1

The Big Bang is a scientific theory about how the universe started, and then made the groups of stars (called galaxies) we see today. The universe began as very hot, small, and dense, with no stars, atoms, form, or structure (called a "singularity").

Answer 2

A theory in astronomy the universe originated billions of years ago in an explosion from a single point of nearly infinite energy density compare
First known big bang theory is use by 1995