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Modern Cosmology and Theology

At the end of his discussion of fine-tuning arguments, Sobel briefly, and somewhat indirectly, discusses issues arising from attempts to combine theism with modern cosmology (pp. 285-287). In particular, many cosmologists now believe that the fundamental constants of nature were set by quantum fluctuations in the early universe. Stephen Hawking has suggested that such fluctuations might be very likely to produce a world like ours. If correct, the thought goes, this would undermine the fine-tuning argument. However, it would also do something more: if the laws of nature make it very likely, but not certain, that a world like ours, capable of supporting life, will come into being, this is a fact that theists will have difficulty explaining. Why did God make probabilistic laws? Would God have intervened if the early fluctuations had gone otherwise? If so, then why didn't he set things up so as to ensure that they came off right without intervention? If not, why did he decide to take this risk? In short, can we make sense of the idea of a god - a literal god, not a figure of speech - who 'plays dice'?

Here I think Sobel, following Quentin Smith, has put his finger on what is perhaps the deepest and most interesting question at the intersection of theology and modern science. (Certainly it is deeper and more interesting than any issue raised by evolution.) However, Sobel fails to mention any possible solution to it. I find it hard to believe that he can't think of any possible solution: there's one right under his nose. One of the main historical figures Sobel has been discussing is Hume, and it seems that if we can develop a Humean (descriptive) theory of natural law which is able to deal with probabilistic laws, then we will have solved, or at least greatly mitigated, the problem. (Of course, this is no easy task!) On such a descriptivist reading, it is possible that although the probabilistic laws of quantum mechanics are the laws of our world, God chooses how each wave-function collapses, and chooses for reasons. All that is required is that those reasons do not lead to regularities of the sort that could displace the quantum laws as the laws of our world. For instance, we might make it a principle of our descriptive theory of laws that physical laws are not teleological. Thus if God chooses that the wave-function collapse a certain way in order that intelligent beings later arise, this does not threaten to replace quantum mechanics with a different set of physical laws.

Note that this is not a 'hidden variable' theory: hidden variable theories say that there is some more fundamental, deterministic physical law behind quantum mechanics, whereas on this view quantum mechanics (or we should rather say: whatever theory of quantum gravity physicists eventually work out, which will no doubt still be indeterministic) is the most fundamental physical law; it's just that there are deeper explanations than physical laws.

This is just one solution. There are probably others. But I was impressed that Sobel pointed out the difficulty, because I think that it is one of the deepest and most interesting difficulties contemporary theists face, and it is far too often ignored.

[Cross-posted at The Prosblogion]