A quite viable theory that states that the universe was at one point a tiny piece of hot mass. At some point, an unknown factor caused this hot piece of matter to explode, causing our universe to be born. The intense explosion is called the "Big Bang". Evidence for this theory exists in the form of Galactic seperation. This is what happens when galaxies repell away from eachother at extreme speeds. I think this is much more plausible than "a great being was bored one day and decided to create the universe"
Christians tell cosmologists to read the bible for the way the universe was created. Might i remind you that the same book stated that this earth was only 6,000 or so years old.