Mind over matter?
December 2008 New Scientist.
WHAT would you rather believe in, God or the multiverse? It sounds like an instance of cosmic apples and oranges, but increasingly we are being told it's a choice we must make. Take the dialogue earlier this year between Richard Dawkins and physicist Steven Weinberg in Austin, Texas. Discussing the fact that the universe appears fine-tuned for our existence, Weinberg told Dawkins: "If you discovered a really impressive fine-tuning... I think you'd really be left with only two explanations: a benevolent designer or a multiverse."
Weinberg went on to clarify that invoking a benevolent designer does not count as a genuine explanation, but I was intrigued by his either/or scenario. Is that really our only choice? Supernatural creator or parallel worlds?
It is according to an article in this month's Discover magazine. "Short of invoking a benevolent creator, many physicists see only one possible explanation," writes journalist Tim Folger. "Our universe may be but one of perhaps infinitely many universes in an inconceivably vast multiverse." Folger quotes cosmologist Bernard Carr: "If you don't want God, you'd better have a multiverse."
There are plenty of reasons to take the multiverse seriously. Three key theories - quantum mechanics, cosmic inflation and string theory - all converge on the idea. But the reason physicists talk about the multiverse as an alternative to God is because it helps explain why the universe is so bio-friendly. From the strength of gravity to the mass of a proton, it's as if the universe were designed just for us. If, however, there are an infinite number of universes - with physical constants that vary from one to the next - our cosy neighbourhood isn't only possible, it's inevitable.
But to suggest that if this theory doesn't pan out our only other option is a supernatural one is to abandon science itself. Not only is it an unfounded leap of logic, it suggests intelligent design offers as valid an explanation as a cosmological theory does, and lends credence to creationists' mistaken claim that the multiverse was invented to serve as science's get-out-of-God-free card. Indeed, Folger's article was immediately referenced on creationist websites, including the Access Research Network, an intelligent-design hub, and Uncommon Descent, the blog of the Seattle-based Discovery Institute's William Dembski.
To make matters worse, physicists are also dragging morality into the picture. In a recent show about the multiverse that aired on the History Channel, physicist Michio Kaku asked: "Why should I obey the law knowing that in some universe if I commit a crime I'm going to get away with it?" The ID community has already tried to draw lines from Darwin to the Holocaust in their attempt to paint rational people as Satan's minions. Are physicists really suggesting that the multiverse gives us licence to commit evil? It's an absurd notion, which moral philosophers have already killed off in other guises.
Pitting the multiverse against religion presents a false dichotomy. Science never boils down to a choice between two alternative explanations. It is always plausible that both are wrong and a third or fourth or fifth will turn out to be correct.
Science never boils down to a straight choice between two explanations
What might a third option look like here? Physicist John Wheeler once offered a suggestion: maybe we should approach cosmic fine-tuning not as a problem but as a clue. Perhaps it is evidence that we somehow endow the universe with certain features by the mere act of observation. It's an idea that Stephen Hawking has been thinking about, too. Hawking advocates what he calls top-down cosmology, in which observers are creating the universe and its entire history right now. If we in some sense create the universe, it is not surprising that the universe is well suited to us.
That's speculative, but at least it's science.
BTS