When St Thomas Aquinas addressed the question of God's existence he could think of only two arguments against his position. On of those arguments was more against the ability of humans to know for certain that God exists, and thee other was the problem of evil (or suffering). Fast forward through the centuries to today, and modern atheists have added little to the problem of evil; at times, they have split suffering and evil into two categories, though generally suffering is classified as a form of evil; and occasionally attempts have been made to refute this or that argument for the existence of God (though a great many of these have been circular at best). Even the "scientific atheists," from Darwin to Russell to Weinberg, Dawkins, and the other "New Atheists" have based their atheism not on science but on the problem of evil.

Enter Stephen Hawking, and perhaps more importantly his follower, Quentin Smith. Hawking, in his Quantom Cosmology, has argued that there is "no place" for God:

"there would be no singularities at which the laws of science broke down and no edge of space-time at which one would have to appeal to God or some new law to set the boundary conditions for space-time . . . The universe would be completely self-contained and not affected by anything outside itself. It would neither be created nor destroyed. It would just BE . . . What place, then, for a creator?" (from "Brief History of Time, pages 136 and 141).

Hawking's physics may make a fine account of the universe's laws, and perhaps they will someday be complete (and even demonstrated correctly) so that there really aren't any singularities, no need for internal boundary conditions. These laws will be able to explain everything about nature except the two most important things. First, they cannot explain why nature exists, and second, they cannot explain why nature obeys such laws. They can only show that nature exists (which should be plainly obvious to anyone) and that nature does obey such laws. This is no mean feat, but it is not the complete picture, for that lies beyond the domain of physics. To quote from the most important physicist of the 19th century, James Maxwell, "One of the severest tests of the scientific mind is to know the limits of the legitimate application of the scientific method."

The real meat of the argument against "classical theism*" is presented by Hawking's disciple, Smith. Smith states that
"It seems to me that a case can be made that Hawking's physical laws are inconsistent with classical theism. I shall develop an argument to this effect in the present paper. Although this argument is not explicit in Hawking's writings, it is arguably implicit in or based upon his theory."

He then proceeds to make this case by arguing that Hawking's theory of the universe--predictions from which have been confirmed via observations from the COBE satellite, among other things--not only removes the necessity of God's existence but rather is an argument against it. He goes so far to say that this argument actually proves that God does not exist.

In essence, his argument is that Hawking's model relies on a wave function for the universe. This is an interesting application of quantum theory, in which virtually everything becomes a wave function, and is determined by probabilities. Smith then goes a step further and states that the wave function gives a 95% probability that the universe would come into existence. Setting aside that this says nothing about the probability of our exact universe coming into being, Smith finds that this 95% chance disproves God:
"Now consider the hypothesis that God ordains that Hawking's wave function law obtains. Assuming this hypothesis, God could create the sort of universe that is most probable or the one that is second most probable, etc., as specified by the law he chose to make obtain. Suppose he decides to create the most probable one. It follows that the universe has a sufficient condition of its existence, not a probabilistic one....God is omnipotent and thus his willing cannot fail to be effective and thus the probability value is 100%."

Overlooked is the possibility that God can will a universe to exist which has an apparent wave function of 95%--even if the universe ultimately has a 100% chance of existing due to the fact that God willed it. Also overlooked is the possibility that Hawking's "95%" calculation might be wrong, smart as the man is (Hawking is omnipotent, and therefore and omnipotent God does not exist). What smith doesn't mention--and what he is certainly well aware of--is that in quantum mechanics, probabilities tend to be somewhat smaller than 100%. The math which underlies quantum mechanics does not permit us to ever be "100% sure" of anything--we can only conclude that something is "(highly) likely to exist or occur."

All of this ignores a very obvious point: the actual probability that the universe does exist is 100%. That the universe had a wave function of 95% probability for its existence is irrelevant next to that fact. Put another way, either the wave function has been collapsed and now has a 100% probability for the universe to exist, or it continues to have a 95% probability of existing, in which case the universe ought to have long since ceased to exist. Thus, it is the will of God which allows the universe to continue existing.

Since the probability of the universe coming into being appears to be 95%, Smith concludes that God must not exist, because otherwise the probability of the universe coming into existence would be 100%. Here is an interesting if somewhat hypothetical question: suppose that the probability of the wave function was 100%; would Smith then argue that it is clear evidence for the existence of God? No, he would not; rather, he would use this as more evidence that God does not exist by arguing that the universe would be self-causing, and hence that there was no need for a First Cause (namely, God).

As an interesting footnote, Hawking's theory suggests that the universe began in a timeless space, much smaller that the nuclei of an atom. Hawking's theory, like most theories about what happened "before" the Big Bang, sets everything in a "timeless" place. Most "Classical Theists" (Christians et al.) believe that heaven is a "timeless place" outside of the universe. Hawking's model predicts the existence of "timeless places," a thing in which Christianity has long since believed.

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*Which he actually gets wrong entirely. See Professor Ed Feser's Posts about "Classical Theism" and "Divine Simplicity," or the Catholic Encyclopedia's entries on the same, for more about this particular point.