Wednesday, September 22, 2010

Equations all the way down

Stephen Hawking is probably the best-known physicist of our day. He is the author of a number of mass-media books about science, including A Brief History of Time, which begins this way:
A well-known scientist (some say it was Bertrand Russell) once gave a public lecture on astronomy. He described how the earth orbits around the sun and how the sun, in turn, orbits around the center of a vast collection of stars called our galaxy. At the end of the lecture, a little old lady at the back of the room got up and said: "What you have told us is rubbish. The world is really a flat plate supported on the back of a giant tortoise." The scientist gave a superior smile before replying, "What is the tortoise standing on?" "You're very clever, young man, very clever", said the old lady. "But it's turtles all the way down!"
The premise of Hawking's latest book, The Grand Design, co-authored with physicist Leonard Mlodinow, strikes me as not much of an improvement of the turtles thesis. Instead of turtles, Hawking has equations.

When the Marquis de Laplace presented his work, Mecanique celeste, to Napoleon, the conqueror complained that LaPlace had not mentioned of God in the text. Laplace replied,"Emperor, I have no need for that hypothesis."

That is the specific premise - nay, the very objective - of The Grand Design, in which Hawking claims that God is not needed to explain the beginning of the universe. "Because there is a law such as gravity, the universe can and will create itself from nothing," writes Hawking. "Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist. It is not necessary to invoke God to light the blue touch paper and set the universe going."

It's striking how much this kind of science is coming to resemble science fiction with its own religious overtones. As Mlodinow is quoted:
We don't have a laboratory where we can control what's going on. We can't repeat the experiment and take the data. Also, the universe — since we believe in quantum theory now — is a quantum system.

What Hawking et al have done is written a form of science fiction, using equations rather than prose. All their equations may work out, but that don't mean they actually know more than before or that reality has been discerned to a greater degree. Hawking admitted that postulating a universe of three or four dimension did not resolve mathematically. In fact, using up to 10 dimensions didn't work. So they tried 11 and presto! X = 0. Or something. To paraphrase Groucho Marx, "These are our equations. If they don’t work, we have others."

It's equations all the way down.

In a sense, of course, all mathematical constructs are fictional, that is, creations of the mind. However, some math is purely theoretical in ways that other math is not. Negative numbers for example, have no real-world referent like positive numbers do. You cannot point to a fruit basket and say meaningfully, "That basket contains minus four apples." Mathematicians themselves even refer to "imaginary numbers." That doesn't mean they aren’t useful, but they are only mathematically useful. The square root of -1 is not a concept that has practical application.

I've no doubt that Hawking is impelled by a childlike curiosity about the universe that is so crucial to scientific work. But Hawking has been trying for years to establish in the popular mind his world view, which is not really a scientific one, but scientistic, a non-confirmable belief that science describes reality exhaustively and absolutely. But the scientific method cannot even demonstrate this, much less subject it to empirical verification. Scientism is a religious-type belief in science. As Mlodinow says, "We believe in quantum theory."

This is really a work of fiction, using numbers rather than prose.
And so Hawking claims that the universe simply popped into existence from nothing whatsoever, resting his claim purely upon mathematical constructs that are no less fictional than seventh-grade quadratic equations.

Yet Hawking may have shored up Genesis’ account as much as attacked it. Theoretical physicist Lawrence Krauss says, "Empirically, we can actually have evidence that the universe came from nothing. One of the key things is that the total energy of the universe is zero, which is only possible if the universe came from nothing. It could have been otherwise. It could have been not zero."

So it would seem that science has confirmed what the Church has claimed since earliest days, creatio ex nihilo, the idea that the universe’s antecedent was nothing at all. (One professor told me that the only reason the Jews didn't write creatio ex nihilo was that they didn't speak Latin.) That being so, a cynic might ask why a fiction of physicists’ equations should be preferred to the fiction of ancient priests' prose, since they both claim basically the same thing. Or perhaps the two accounts are not so separate as we think. Richard Feynman, after all, said that calculus, the basic math of physics, was, "the language God talks."

I prefer the priestly account of creation to Hawking's, since, as Mlodinow pretty much admitted, Hawking's and his concept of the universe's "grand design" is at bottom conjecture. Scientists may be able to describe how I got here, but not why. They can say what we can do, but not what we should do. Mlodinow said that there is no laboratory to research the universe’s beginning. But we live in a real-world lab with certain consequences. So we are better off heeding the wisdom of the prose than the conjecture of equations, even if they are equally false, or true.

Closing thought: Why is Hawking so willing to assume that the universe simply "big banged" itself into existence when we deny that anything else does so? And if the universe simply appeared, just popped into being, why do other such appearances not happen routinely? Why, for example, don't spherical balls (or whatever) just pop up in my front yard or yours from time to time?

But they don't. In fact, the entire universe itself consists only of contingent events that bring forth only contingent entities. But somehow, Hawking is nonetheless willing to say that the universe alone is a necessary entity. I wrote at some length about this argument in "Why God Must Exist."