As intelligent-design-based opposition to science slowly dissolves, its adherents are rushing to find arguments for God in another field—physics. I hear these arguments all the time when I’m on the road, and encountered them again this week in Maryland. They boil down to three assertions:

The “fine-tuning” argument. The physical constants of the universe are tightly constrained, for if they varied even a little, life wouldn’t be here. Ergo Jesus. The “why there are laws” argument. We have no explanation for why there are laws of physics that hold throughout the universe. Presumably, without God there would be no “laws” at all. Ergo Jesus. A variant of this argument, made by people like Kenneth Miller, is the “science works” argument: because the universe is intelligible by human exploration and rationality, it must have been constructed by God. Note, too, the similarity of this argument to the “moral law” argument that we see frequently: people have an innate morality, and that innateness is evidence for God. Francis Collins, director of the National Institutes of Health, sees this “Moral Law” argument as perhaps the most powerful evidence for God. (It’s not of course: “innateness” could reflect evolutionary wiring, universal instruction or a combination of both.) The Big Bang argument. This is a just a fancy scientific update of the old Cosmological Argument that everything has a cause, and the ultimate cause must be God. In the case of physics, the argument goes like this: maybe physics can understand how the universe came from the Big Bang, but what was there before the Bang? How could something come from nothing?

Many of us are familiar with the rebuttals to these arguments, some of which have been published by Victor Stenger and Steven Weinberg. But since these claims keep coming up, and are likely to form the most common science-based support for God, it behooves us to understand why they don’t hold water.

In some discussion with physicist Sean Carroll about these issues, he referred me to a very nice piece he wrote for the upcoming Blackwell Companion to Science and Christianity, “Does the universe need God“? In his characteristically lucid prose, Carroll deals with all three of the arguments given above. I was especially interested in Big Bang arguments, which is why I wrote Sean in the first place. Carroll explains some of the theories for the origin of the universe, emphasizing this:

The singularity at the Big Bang doesn’t indicate a beginning to the universe, only an end to our theoretical comprehension. It may be that this moment does indeed correspond to a beginning, and a complete theory of quantum gravity will eventually explain how the universe started at approximately this time. But it is equally plausible that what we think of as the Big Bang is merely a phase in the history of the universe, which stretches long before that time – perhaps infinitely far in the past. The present state of the art is simply insufficient to decide between these alternatives; to do so, we will need to formulate and test a working theory of quantum gravity. . . . . . There are a number of avenues currently being explored by physicists that hope to provide a complete and self-contained account of the universe, including the Big Bang. Roughly speaking they can be divided into two types: “beginning” cosmologies, in which there is a first moment of time, and “eternal” cosmologies, where time stretches to the past without limit. . . . . .A provocative way of characterizing these beginning cosmologies is to say that “the universe was created from nothing.” Much debate has gone into deciding what this claim is supposed to mean. Unfortunately, it is a fairly misleading natural-language translation of a concept that is not completely well-defined even at the technical level. Terms that are imprecisely defined include “universe,” “created,” “from,” and “nothing.” (We can argue about “was.”) The problem with “creation from nothing” is that it conjures an image of a pre-existing “nothingness” out of which the universe spontaneously appeared – not at all what is actually involved in this idea. Partly this is because, as human beings embedded in a universe with an arrow of time, we can’t help but try to explain events in terms of earlier events, even when the event we are trying to explain is explicitly stated to be the earliest one. It would be more accurate to characterize these models by saying “there was a time such that there was no earlier time.” To make sense of this, it is helpful to think of the present state of the universe and work backwards, rather than succumbing to the temptation to place our imaginations “before” the universe came into being. The beginning cosmologies posit that our mental journey backwards in time will ultimately reach a point past which the concept of “time” is no longer applicable. Alternatively, imagine a universe that collapsed into a Big Crunch, so that there was a future end point to time. We aren’t tempted to say that such a universe “transformed into nothing”; it simply has a final moment of its existence. What actually happens at such a boundary point depends, of course, on the correct quantum theory of gravity.

This is fascinating stuff, taking us to the very edge of modern physics. And it belies the Jebus-lovers’ assertion—one that I encountered on Monday—that scientists simply have “faith” that the universe came from nothing. No, we don’t have faith that it did, we have hypotheses about how it did, and some of those hypotheses are or will be testable. The God explanation, of course, is not testable—it’s just a refuge for nescience.

Carroll goes on to examine the fine-tuning and multiverse arguments, some of which are also testable. He emphasizes that multiverse theory is not a Hail Mary pass thrown by God-beleaguered physicists, but a natural outcome of modern research:

The multiverse is not a theory; it is a prediction of a theory, namely the combination of inflationary cosmology and a landscape of vacuum states. Both of these ideas came about for other reasons, having nothing to do with the multiverse. If they are right, they predict the existence of a multiverse in a wide variety of circumstances. It’s our job to take the predictions of our theories seriously, not to discount them because we end up with an uncomfortably large number of universes.

But go read the piece. It ends with a nice discussion of why physicists who are exploring cosmological boundaries aren’t tempted by the God Hypothesis. A nice snippet:

Ambitious approaches to contemporary cosmological questions, such as quantum cosmology, the multiverse, and the anthropic principle, have not yet been developed into mature scientific theories. But the advocates of these schemes are working hard to derive testable predictions on the basis of their ideas: for the amplitude of cosmological perturbations,[29] signals of colliding pocket universes in the cosmic microwave background,[30] and the mass of the Higgs boson and other particles.[31] For the God hypothesis, it is unclear where one would start. Why does God favor three generations of elementary particles, with a wide spectrum of masses? Would God use supersymmetry or strong dynamics to stabilize the hierarchy between the weak scale and the Planck scale, or simply set it that way by hand? What would God’s favorite dark matter particle be? This is a venerable problem, reaching far beyond natural theology. In numerous ways, the world around us is more like what we would expect from a dysteleological set of uncaring laws of nature than from a higher power with an interest in our welfare. As another thought experiment, imagine a hypothetical world in which there was no evil, people were invariably kind, fewer natural disasters occurred, and virtue was always rewarded. Would inhabitants of that world consider these features to be evidence against the existence of God? If not, why don’t we consider the contrary conditions to be such evidence?

Indeed! If, as liberal theologians tell us, the “necessary” evils of this world are exactly what God would produce given his penchant for human free will and for physical “freedom” like the movement of tectonic plates, then would a nicer world disprove the God Hypothesis? Don’t hold your breath, for the nature of the God Hypothesis is that no observation could ever disprove it. That’s why it’s not scientific at all, and why religion and science will never find an amiable concordat.