Big Bang Theory

                                                                                                    This is a picture of the universe in the beginning of time.

The Theory
The name itself, is not at all what the Big bang Theory actually was. There was no air when the Big Bang took place. In fact, it was not big, it was very small. There was no "Big Bang" because it wasn't loud.
Big Bang took place about 13.7 billion years ago. Scientists believe that it started with a "singularity" ( Thought to be the center of black holes) and thats where it all began. The universe also began with 90% of hydrogen and  10% helium. Many elements were created when the Big Bang took place, and protons and neutrons were created. As millions of years went on, the universe it began to expand and cool down. It went from going very, very small and very, very hot to the universe we have today.