A universe from nothing? (Or, Craig/Vilenkin part 5)

I deconverted from Christianity mainly because of its theological absurdity (see the previous post for an example), but it took another nine years or so before I considered myself an atheist. I held on to a sort of agnostic theism simply because "God" seemed like an intellectually satisfying answer to some of the most vexing questions we can think of – questions like Why is there something rather than nothing?, Where did the universe come from?, How did life get so complex?, or Why does altruism exist? Certainly those are vexing questions for scientists and laypersons alike, and just saying "because God made it that way" certainly takes most... well, actually all of the thought out of it.

But as time went on, I began to realize the vacuity of that "explanation". If God wants to create life, why create a universe so hostile to it? Why take nearly 14 billion years to do it? Why an expanding universe rocketing toward a slow, empty death? Why use the process of evolution at all, or wipe out over 99% of all species that ever lived on Earth (to say nothing of the fate of life elsewhere in the universe)?

As I mulled over these difficult questions of faith, I spent a lot of time reading Wikipedia articles about cosmology. Much of it stemmed from a comment that was unsettling to me during an internet debate between me and an atheist back in 2007. Here's the exchange, with the quoted part being mine. (Btw, if you ever want to see me defend theism and lose badly, the full exchange is here.)



Nevermind my misspelling of the word "tenet"... Much of my perspective changed when I read Stephen Hawking's bestseller A Brief History of Time. The question of the origin of the universe vexed him also, but being a physicist he pondered an interesting idea: what if the universe was enclosed and could be described with the laws of mathematics, instead of needing some sort of external cause? From there he discussed the Hawking-Hartle No Boundary Proposal, in which he describes a universe that, like the surface of the Earth, is finite but has no boundary or edge. With no boundary, there is no moment of creation – the universe would simply be.

Of course, Hawking's idea was (and is) just a proposal. We don't know if it's true. But as you can easily tell from some of my comments in the above debate (should you read it), I had stubbornly assumed that the universe logically had to have some sort of external cause to bring it into existence. The simple idea that an enclosed universe fits within the known laws of physics humbled my position into one with many uncertainties – uncertainties exacerbated by the logical conundrums of causality somehow applying "to" the universe (for without a universe, what is causality at all?).



I'm telling you all this because Alexander Vilenkin, in Many Worlds in One, details an idea similar to Hawking's. Similar in some ways, but different in the sense that Vilenkin seems to take it a step further. I'll spare you the details (read the book!), but his model is a quantum-tunneling process. The universe is essentially "nothing" – there is no space, no time, no matter or energy. And yet, in Vilenkin's model, the laws of physics would still somehow exist. He explains:
The picture of quantum tunneling from nothing raises another intriguing question. The tunneling process is governed by the same fundamental laws that describe the subsequent evolution of the universe. It follows that the laws should be “there” even prior to the universe itself. Does this mean that the laws are not mere descriptions of reality and can have an independent existence of their own? In the absence of space, time, and matter, what tablets could they be written upon? The laws are expressed in the form of mathematical equations. If the medium of mathematics is the mind, does this mean that mind should predate the universe? This takes us far into the unknown, all the way to the abyss of great mystery. It is hard to imagine how we can ever get past this point. But as before, that may just reflect the limits of our imagination.
William Lane Craig, in his review of the book, predictably doesn't take too kindly to speculative physics that have the potential to remove the usefulness of God:
Vilenkin himself seems to realize that he has not really described the tunneling of the universe from literally nothing, for he allows, "And yet, the state of 'nothing' cannot be identified with absolute nothingness. The tunneling is described by the laws of quantum mechanics, and thus 'nothing' should be subjected to these laws" (p. 181). It follows that the universe described by those laws is not nothing. Unfortunately, Vilenkin draws the mistaken inference that "The laws of physics must have existed, even though there was no universe" (p. 181). Even if one takes a Platonistic view of the laws of nature, they are at most either mathematical objects or propositions, abstract entities that have no effect on anything. (Intriguingly, Vilenkin entertains a conceptualist view according to which the laws exist in a mind which predates the universe [p. 205], the closest Vilenkin comes to theism). If these laws are truly descriptive, then obviously it cannot be true that "there was no universe."
Some of this is just theological sophistry. It's irrelevant whether Vilenkin's use of the term "nothing" is identical to Craig's (which it's obviously not). "Absolute nothingness" is an absolutely useless construct, since such a thing cannot even be conceived in any logical way, much less described mathematically. Vilenkin's model is the closest we get to "nothing". 

For my part, there's a simplicity to Hawking's model that I find a bit more appealing. (It should again come as no surprise that Craig doesn't like Hawking's model either.) It's difficult to imagine how the laws of physics might "exist" – they would have to be proscriptive, not merely descriptive. But on the other hand, it's foolhardy to dismiss a mathematical model simply because it's counter-intuitive or because it challenges us with concepts that are difficult to imagine. I haven't the slightest clue whether Vilenkin's model is correct, and he cautions that this sort of cosmology may be in principle untestable. I'm reminded of Stephen Hawking's concept of model-dependent realism: it's meaningless to ask what is real – only what is the more useful description of reality. In what sense are the laws of physics "real"? Who knows. I also cannot help but give the Hawking-Hartle proposal a slight edge, simply because it made a confirmed prediction about the observable universe:
Eventually, the period of inflation would have ended, and the universe would have settled down to a stage of more moderate growth or expansion. However, inflation would have left its mark on the universe. The universe would have been almost completely smooth, but with very slight irregularities. These irregularities are so little, only one part in a hundred thousand, that for years people looked for them in vain. But in 1992, the Cosmic Background Explorer satellite, COBE, found these irregularities in the microwave background radiation. It was an historic moment. We saw back to the origin of the universe. The form of the fluctuations in the microwave background agree closely with the predictions of the no boundary proposal.
That's one more confirmed prediction than any Goddidit hypothesis. Sure, we can never disprove the existence of some sort of God. We may never be able to conclusively establish a No Boundary universe or a "universe from nothing". But the available evidence simply does not compel us to believe in any sort of Creator, and as a theist I found that very disconcerting.

This is actually reflected in Craig's language in his review of Vilenkin's book – he moves away from the cocksure language of his debates and into more conciliatory tone. Take this quote, which I mentioned in the previous part:
[If] Vilenkin's theory of quantum tunneling provides an account of how the universe can arise without a material cause, then the theist may freely avail himself of it also. The advantage of theism over naturalistic accounts is that theism provides an efficient cause of the universe, whereas naturalism cannot.
That's like saying, "the advantage of believing in God is that you can accept the idea of a scientific explanation for the origin of the universe, but still believe God had some sort of inexplicable role in its creation". The ideas presented here don't render God non-existent; they render God irrelevant. As I often say: the only thing worse than a God who doesn't exist is one who might as well not exist.

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