Sunday, October 03, 2010

Hawking off the Reservation Again

The media have been aflurry with Hawking's latest pronouncement. The Wall Street Journal features an excerpt of his recently published book The Grand Design, written with Leonard Mlodinow. Here's an excerpt of that excerpt:

Newton believed that our strangely habitable solar system did not "arise out of chaos by the mere laws of nature." Instead, he maintained that the order in the universe was "created by God at first and conserved by him to this Day in the same state and condition." The discovery recently of the extreme fine-tuning of so many laws of nature could lead some back to the idea that this grand design is the work of some grand Designer. Yet the latest advances in cosmology explain why the laws of the universe seem tailor-made for humans, without the need for a benevolent creator.

(But why not a malevolent creator?)

Hawking then reviews the so-called anthropic coincidences—the apparent fine tuning of constants in our mathematical laws of physics—without which the human life, or even the continued existence of the universe itself would be impossible.

Many people would like us to use these [anthropic] coincidences as evidence of the work of God. The idea that the universe was designed to accommodate mankind appears in theologies and mythologies dating from thousands of years ago. In Western culture the Old Testament contains the idea of providential design, but the traditional Christian viewpoint was also greatly influenced by Aristotle, who believed "in an intelligent natural world that functions according to some deliberate design."

[If the universe weren't intelligent in some sense, then how could intelligence discover its rules?]

That is not the answer of modern science. As recent advances in cosmology suggest, the laws of gravity and quantum theory allow universes to appear spontaneously from nothing. 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.

Our universe seems to be one of many, each with different laws. That multiverse idea is not a notion invented to account for the miracle of fine tuning. It is a consequence predicted by many theories in modern cosmology. If it is true it reduces the strong anthropic principle to the weak one, putting the fine tunings of physical law on the same footing as the environmental factors, for it means that our cosmic habitat—now the entire observable universe—is just one of many.

Each universe has many possible histories and many possible states. Only a very few would allow creatures like us to exist. Although we are puny and insignificant on the scale of the cosmos, this makes us in a sense the lords of creation.

As soon as Hawking invokes the word "creation," he's departed physics for metaphysics. Physics of any kind can only study things that move. Creation is not a motion: something either exists or it doesn't. There is no motion between the two discrete states of being and non-being. Mathematical physics can't even handle the concept "nothing" (of course zero is not nothing).

How could nothing (really nothing) generate something? Hawking is using "nothing" equivocally. Perhaps this fuzzy mode of thinking descends from Newton's equivocal use of zero in calculus (at once and in the same expression the variable is zero in one instance, while in another it's non-zero). Or perhaps it's just another manifestation of perennial fuzzy thinking inspired by the consequentialism of the hypothetical-deductive model of science.

Hawking might ask himself how the multiverse exists. And on what basis does Hawking presume the laws of physics1 are self-existent?

"Off the reservation" is a phrase that means "gone rogue." Stephen Hawking hasn't so much gone rogue as shown once again that he is unable to restrict himself to the territory of physics at which he is so adept. He insists on trespassing outside to a subject he shows no evidence of ever having studied seriously: philosophy. Without a serious study of this subject (or at least consulting real experts), Hawking can only pull his ideas from the winds of unreflective (pop) culture: a disappointing performance from a world-class intellect.

Of course the whole controversy (like so many in the media) is a tempest in a tea-pot. Why should anyone care what Hawking says about any random (i.e., non-physics) subject? Xkcd pegs it in this insightful cartoon.


1. Hawking was much wiser when he wrote: "Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire in the equations and makes a universe for them to describe? The usual approach of science of constructing a mathematical model cannot answer the questions of why there should be a universe for the model to describe. Why does the universe go to all the bother of existing?"

Stephen Hawking and Leonard Mlodinow, The Grand Design (Bantam, 2010).

Update (2010-10-05): One can hardly do better than William E. Carroll in addressing the philosophical issues Hawking raises, as in this passage:

Creation is not primarily some distant event. Rather, it is the ongoing, complete causing of the existence of all that is. At this very moment, were God not causing all that is to exist, there would be nothing at all. Creation concerns the origin of the universe, not its temporal beginning. Indeed, it is important to recognize this distinction between origin and beginning. The former affirms the complete, continuing dependence of all that is on God as cause. It may very well be that the universe had a temporal beginning, but there is no contradiction in the notion of an eternal, created universe, for were the universe to be without a beginning it still would have an origin; it still would be created. This is precisely the position of Thomas Aquinas, who accepted as a matter of faith that the universe had a temporal beginning but also defended the intelligibility of a universe simultaneously created and eternal. ("Stephen Hawking’s Creation Confusion")