Stephen Hawking thinks he knows what happened before the big bang

Any time you hear a scientists talk about the origins of the universe it always begins the same way. "It all started with the big bang," they say, and from there humanity has built a rough timeline of the events that led us to today. But what about before the big bang? You rarely hear physicists attempt to explain it, but renowned thinker Stephen Hawking believes he has the answer. As you might imagine, it's not the easiest thing to grasp. Talking with Neil deGrasse Tyson on his popular Star Tal...