William Lane Craig vs. Sean Carroll on the Beginning of the Universe!

Sean Carroll and others have proposed beginningless models of the universe, but is there actually any evidence for any of these models? Dr. Craig responds!

FRANK: Bill, you've also debated Sean Carroll. What is his position on the origin of the universe, and how would you respond to it?

DR. CRAIG: I think he would be agnostic about the second premise, that the universe began to exist. I think he would say that there are viable models of the universe which are past-eternal and beginningless, but he's hard-pressed to come up with any of them. His own model, the Carroll-Chen model, doesn't do the trick; it has to involve a reversal of the arrow of time at some point in the past where the arrow of time flips over and runs in the opposite direction so that you have a kind of mirror universe prior to ours. But the difficulty with that is that mirror universe isn't temporarily prior to ours because the arrow of time runs in the opposite direction. What you really have is two universes with a common origin, rather than a past-eternal universe. So Caroll wants to hold out hope for a beginningless, past-eternal model, but so far he hasn't been able to come up with them, nor has anyone else.

FRANK: Can you help our audience with the difference between a “model” (like, say, Caroll is bringing) and evidence for a theory. Because you can have a model that doesn't have any sort of connection to reality.

DR. CRAIG: Oh, absolutely. And a great example of that would be Roger Penrose's Conformal Cyclical Cosmology. It's a mathematical model of the universe and its origin, but it's utterly unconnected with physical evidence. Not only is there no physical evidence in support of it, but he actually has to use a kind of alien physics that isn't descriptive of our universe in order to make the model work. So it's a purely mathematical model that has no connection with the world in which we actually live.