Tuesday, 2 November 2010

Hawking versus God

(Article by Sylvestre Huet in Libération)

In his latest book, the English physicist Stephen Hawking responds to the proponents of 'intelligent design' by claiming that the existence of the universe follows from the laws of physics alone. Philosophy or marketing stunt? How does one sell several million copies of a book on the cutting edge of physics and modern cosmology? Here's the recipe, concocted and certified by multinational publisers Bantam Press.

One: highlight the name of Stephen Hawking in large letters on the cover. Yes, that of the author of the bestseller A Brief History of Time (almost 10 million copies sold since 1988). The English physicist, occupant of the Chair of Newton at Cambridge, who has experienced the agony of a terrible disease (neuromuscular dystrophy), confined to a wheelchair for over thirty-five years, deprived of speech and today of all movement. And gloss over the co-writer Leonard Mlodinow, in smaller letters on the cover.

A media strategy from hell

Two: the title, The Grand Design. With the subtitle New Answers to the Ultimate Questions of Life. Is this the work of a guru? With recipes for living and transcendental meditation? Yes, and it's good for sales. Selling the idea that physics has the answer to existential questions sounds crazy, but it works.

Three: insert a sentence with the word "God" in it. In A Brief History of Time, this was to assert that the future Theory of Everything (in capitals) would allow us to access "the thoughts of God." Something that would earn you a harsh note in a philosophy exam paper. Here, the opposite, or nearly so. This sentence is, of course, on the penultimate page of the book (page 180): "Because there are laws like gravity, the universe can and must create itself from nothing. [...] Spontaneous creation is the reason why there is something rather than nothing, why the universe exists, why we exist. There is no need to invoke God to press the 'on' button and start the universe."

Four: a media strategy from hell. With articles on the front pages of the English and American press, based solely on that small sentence. The newspapers will lend themselves to the marketing operation, because if God sells, attacks on God sell even more. So controversy is guaranteed, since religious leaders answer to the call of the media. As is already the case with the Archbishop of Canterbury. Financial bingo. 'Thank you, Stephen' whisper his entourage and his publisher inaudibly.

If this fuss was serving a good cause - spreading science and philosophy of science among the general public - it would be possible to consider these sins forgiven. But no. Science, like philosophy, emerges from the process disfigured.

Philosophy? A college lecturer in this discipline, Jean-François Robredo, is surprised: "Since Galileo, philosophers and scientists have known that mixing, as well as opposing, science and religion is fruitless. The Church wanted to protect itself by relegating science to the realm of the hypothetical, in order to deny the evidence and preserve the literal truth of the sacred texts. This is the attitude of creationists and proponents of Intelligent Design. In the inverse case, equally barren and dangerous: Pope Pius XII tried to match the Genesis cosmology with big-bang cosmology. Stephen Hawking, in speaking yesterday of the thoughts of God, and today of denial of God, commits the same old error twice over."

The physicist Etienne Klein speaks out: "The comments attributed to Hawking are astonishingly naive; the degree-zero of epistemology, a long way from the subtlety and intelligence he has shown in physics. To demonstrate that God is not necessary, one must first say very clearly who that Being is whose futility we wish to prove. 'God' can be many different things ... But Hawking does not tell us what God he is talking about." Then he quips: "If gravity is sufficient to create the universe, why not say that gravity is God? Any fall would therefore be a transcendental experience."

Philosophers know how to talk about the origin of the universe. If this origin is transcendent, it is outside the universe, and signifies the transition from nothingness to being, you can call it anything you want, God or whatever; this is not a question for science. And Leibnitz's question - "Why is there something rather than nothing?" - has no more intellectual force for the scientific approach than its opposite - "Why would there have been nothing, why would the universe not always have existed? "

If the origin of the observable universe is immanent to it, it is part of it and could then, in principle, be the object of science. That is what Hawking seems to say that when he claims that the universe arises from itself. Except that when you read him carefully, he makes it arise from a 'nothing' which contains... the laws of gravity - more precisely the M-theory unifying gravity and quantum theory. This statement is self-contradicting, since this nothing would already be inhabited... by the said laws.

Intellectual blunder

"Where does it come from?" asks Etienne Klein ironically, who highlights the "fundamental contradiction involved in making the universe arise from nothing ... This involves conferring properties to this nothing." This implies furthermore that these laws predate the inseparable trio matter-space-time of physics and contemporary cosmology. As if a set of mathematical equations could become a physical universe. However, as the physicist Michel Spiro (President of CERN) modestly reminds us, "our theories of physics expressed in mathematical language are the product of human activity. And even maths, as shown by Kurt Gödel's theorem of incompleteness, does not arise of itself, it rests on unprovable axioms."

The intellectual blunder in Hawking's book is not original or new. "The confusion between scientific knowledge and religious vocabulary is old and persistent," said the epistemologist Michel Paty. A confusion perpetuated by physicists who have not hesitated to baptise the Higgs boson being investigated at CERN, in the most powerful particle accelerator on earth, the LHC (Large Hadron Collider), the 'God particle'. For him, Stephen Hawking's assertion represents "a regression in rational thinking. Scientific and philosophical thought should not entertain this meddling with religion."
If the book penned by Hawking abuses philosophy, it does not treat contemporary physics any better, in spite of beautiful passages. "Physics and cosmology," says Michel Spiro, "have been able to tell the saga of the universe we live in over 13.7 billion years." But this scientific cosmogony does not answer the question of its origin, not even in a limited rational sense. "Going back through the history of our universe, towards the very dense, very hot phase, our physical concepts come up against their limits. They cannot exceed the Planck wall, 10-43 seconds after the Big Bang. These concepts - general relativity and quantum theory - give rise to infinite values in the equations for the temperature and density of the universe. Such infinities have no physical sense. Thus they indicate the bankruptcy of these theories at these levels of time and energy. As for our experiments, the most powerful conducted with the LHC, they do not pass beyond 10-13 seconds after the Big Bang."

However, Hawking presents the M-theory, unifying gravitation and electromagnetic and nuclear forces, as "the theory sought in vain by Einstein" and "the" answer to this conundrum. This assertion is a scam. The M-theory "is a program of research," retorts Etienne Klein. It is, says Michel Spiro, part of the "theoretical scaffolding built to try to go beyond physics and theories validated by experiment and observation. There are others. There is no evidence that it is more likely than others to withstand experimental refutation." A refutation currently beyond the reach of physicists, and likely to remain so.

Astrophysicist Alain Blanchard therefore calls for caution in writings and the media. "These theories are at the speculative stage, more open as they approach the Big Bang, and more open still if you want to go beyond it. We are reduced to hypotheses about the physics that prevails there. An emphasis on the difference between speculation and theory is therefore required if one wants to popularise the scientific approach, especially since the public has shown itself receptive on the subject of origins."

Why does Hawking present the M-theory as accomplished? Because it coincides with another highly questionable choice: to present as the one and only valid interpretation of quantum physics, that of the 'multiverse'. According to this interpretation, elementary particles, like the universe, realise all the probable outcomes of quantum randomness. Since M-theory states that there 10500 different possible universes, so they all exist. And offer as many different values for the constants of physics (interactive force or particle mass).

This choice is shared by other theorists, but is considered an epistemological weakness by Michel Paty. The theory cannot be refuted by experiment and observation, but is appealing as it answers a question described by Michel Spiro: "How is it that the values of the fundamental constants of physics are precisely those that make the universe capable of harbouring life, although they seem to arise from quantum randomness and not from the necessity of deterministic laws?"

"The infinity of failed universes"

Some answer this question with God. Others hide behind the Intelligent Design echoed by Hawking's Grand Design. Or advance an 'anthropic principle' guiding the determination of physical constants, to allow the emergence of man, a rudimentary finality.

Hawking's book develops a symmetrical argument: since so many universes exist, it is not surprising to find one whose characteristics allow Earth, life and man ... Therefore God does not exist.

Jean-François Robredo stresses the logical impasse. "The multiverse theory cannot conclude the existence or nonexistence of God. It explains our universe as a 'successful' attempt, but not the infinity of 'failed' universes. The divine hypothesis claims to explain everything. Quantity, even if unnecessary, must be explained and justified. To the question of why so many failed attempts, the believer answers: why not?"

The agnostic, for his part, may laugh at such an inept God. Still there is a loser: the reader, who could expect to better understand contemporary science, its methods, its results and its epistemology.

(Translation: A Curran)

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