Evidence Part 4: Cosmology

In the last part we covered the big bang theory, and what it really says, and what it does not say. Before the big bang theory cosmologists believed that the universe was eternal, having no beginning and no end. The big bang theory changed all that. It showed that the universe had a beginning, and it looks like science may never be able to tell us if it has an end (of course, if it does end we will have an answer - reminds me of the halting problem in information theory).

Since the big bang gained enough evidence to be irrefutable, cosmologists have continued to look for ways to get back to an eternal universe, that does not "need" God. Understand that none of these hypotheses are the result of trying to explain observations (like the big bag theory, and like how science is supposed to work), but are proposals to come up with a ways to explain the universe without needing God. They can, in general, neither be confirmed nor refuted because they do not make any claims about our universe, just ideas that maybe there is no God.

All of them are some variation on the multiverse. Our universe is one of an infinite numbers of universes, either parallel in time (parallel universes), or serially in time (bouncing universe). The claim is that since there are an infinite number of universes, any argument for God from design can be refuted by saying "all possibilities exist, it just so happens that this one is this way" (parallel universes) and any argument from existence can be refuted by saying "the universe arose from the previous universe (bouncing universe).

Of course, the bouncing universe suffers from what Stephen Hawking describes as "turtles all the way down." An infinite regression still doesn't explain its own existence. There is a lot more that could be said about parallel universes except I'll leave you with these two thoughts, either of which invalidates the use of the multiverse to get around the need for God.

The first is this. If there are an infinite number of universes and they all work differently, what's to say that the fundamental laws of physics are the same in all of them? If they are, then where did those laws come from? And if not, then what laws are the same in all universes, and where did those laws come from? Or, if you want to admit no fixed laws, and everything that could conceivably exists exists somewhere, then God exists, QED.

But if you don't like thought experiments, consider the Borde-Guth-Vilenkin theorem, which has, for the most part, been unnoticed, but is largely unrefuted as well. It states that any universe or multiverse in which any member universe has a Hubble constant greater than zero (in other words is expanding), has a beginning. The Hubble constant of our universe is greater than zero. Therefore our universe, or the multiverse, if our universe is part of one, had a beginning. Vilenkin says of this theorem:

A remarkable thing about this theorem is its sweeping generality. We made no assumptions about the material content of the universe. We did not even assume that gravity is described by Einstein’s equations. So, if Einstein’s gravity requires some modification, our conclusion will still hold. The only assumption that we made was that the expansion rate of the universe never gets below some nonzero value, no matter how small.

It is said that an argument is what convinces reasonable men and a proof is what it takes to convince even an unreasonable man. With the proof now in place, cosmologists can no longer hide behind the possibility of a past-eternal universe. There is no escape: they have to face the problem of a cosmic beginning.

OK, so the universe had a beginning. So what does that have to do with proving God's existence? We'll take that up in the next post, starting with contingency...

Posted in: atheism,God