Labels:text | screenshot | flower OCR: BIG-BANG THEORY THE BIG-BANG MODEL is currently the only widely accepted explanation for the origin of the Universe. The Big Bang itself was extremely hot and energetic, and in the first few seconds after the explosion all that existed in the Universe was radiation and various subatomic particles. The radiation left over after the explosion is still detectable from Earth as faint microwaves emanating from all directions of the sky. This is called the cosmic microwave background radiation. THE FIRST TWO SECONDS The Universe was once smaller than the nucleus of an atom. EXPANDING END OF THE EVIDENCE FOR UNIVERSE UNIVERSE? THE BIG BANG
