Since then, the Steady State Theory has been disproven, and the Big Bang Theory has been shown to be correct, vindicating a form of «
Creationism», which not only explains «let there be light» (the early universe was
dominated by radiation — light), but explains of separation of light and darkness — the decoupling era, about 300,000
earth years after the big bang, when the universe cooled below the ionization energy of hydrogen, allowing it to become transparent for the first time.