FAITH Magazine May – June 2011
Science and Religion News
The Atheistic Spin on Quantum Theory
At the Faith Theological Symposium in February, Fr Stephen Dingley presented a critique of the recently published The Grand Design by Stephen Hawking and Leonard Mlodinow. In the book, they try to argue for a spontaneous creation of the universe that requires no explanation or origin. Yet, as was pointed out, Hawking and Mlodinow already concede that, for their ideas to work, a law such as gravity has to exist, and thus their "spontaneous creation" is not as "spontaneous" as they claim. Their book is riddled with bad logic and gives rise to false conclusions.
More importantly, it raises the perennial question of the correct interpretation of quantum mechanics (QM). As well as the above irrationality Hawking and Mlodinow rely upon the "Copenhagen" interpretation of QM to establish their "uncaused" cosmos. The Copenhagen interpretation claims that there is a fundamental indeterminism at the base of all reality. Yet this leaves many questions unanswered, and numerous physicists of the 20th century, including Einstein, were not convinced that it was the whole picture.
However, an alternative to the Copenhagen interpretation of QM does exist, developed by the American-born British physicist David Bohm. In his early research career, Bohm worked with Einstein in Princeton. Soon after this, in about 1952, he developed a "hidden variables" interpretation of QM, which is in some ways a redevelopment of ideas already considered in 1927 by Louis de Broglie (see our November 2005 editorial for our discussion of de Broglie's helpful 1939 interpretation of QM). In chapter 4 of his book of essays summing up his life's work, Wholeness and the Implicate Order (1980), David Bohm explains the background to the problem:
"From the fact that quantum theory agrees with experiment in so wide a domain ..., it is evident that the indeterministic features of quantum mechanics are in some way a reflection of the real behaviour of matter in the atomic and nuclear domains, but here the question arises as to just how to interpret this indeterminism" (p. 86).
He goes on to remind us that "lawlessness of individual behaviour in the context of a given statistical law is, in general, consistent with the notion of more detailed individual laws applying in a broader context" (p. 87). His "hidden-variables" interpretation is precisely that search for an underlying ("hidden") law that makes the higher-level indeterminism only apparent.
Despite the majority of physicists' opinions having traditionally been against the existence of hidden variables - since Bohr and Heisenberg in fact - Bohm showed in his work in the 1950s that the objections to a hidden-variable theory were not valid.
He suggested that in the wave/particle nature of matter, it is not that matter behaves sometimes as a wave, and sometimes as a particle (the so-called "wave-particle duality") but that in fact both particle and wave really exist: it is the "pilot" or "guiding" wave that determines the particle's motion. John Stewart Bell, an Irish physicist who did much work in this area, became increasingly attracted to Bohm's formulation and, three years before his death, explained how it works in the case of the traditional two-slit experiment in his book, Speakable and Unspeakable in Quantum Mechanics (1987):
"Is it not clear from the smallness of the scintillation on the screen that we have to do with a particle? And is it not clear, from the diffraction and interference patterns, that the motion of the particle is directed by a wave? De Broglie showed in detail how the motion of a particle, passing through just one of two holes in a screen, could be influenced by waves propagating through both holes. And so influenced that the particle does not go where the waves cancel out, but is attracted to where they cooperate. This idea seems to me so natural and simple, to resolve the wave-particle dilemma in such a clear and ordinary way, that it is a great mystery to me that it was so generally ignored" (p. 191).
Bell reacted strongly to the seeming "suppression" of the successes of hidden-variable work. In the same book he wrote:
"In 1952 I saw the impossible done. It was in papers by David Bohm. Bohm showed explicitly how parameters could indeed be introduced, into non-relativistic wave mechanics, with the help of which the indeterministic description could be transformed into a deterministic one. More importantly, in my opinion, the subjectivity of the orthodox version, the necessary reference to the 'observer,' could be eliminated. ... But why then had Born [a colleague of de Broglie] not told me of this 'pilot wave'? If only to point out what was wrong with it? Why did von Neumann not consider it? More extraordinarily, why did people go on producing 'impossibility' proofs, after 1952, and as recently as 1978? ... Why is the pilot wave picture ignored in text books? Should it not be taught, not as the only way,but as an antidote to the prevailing complacency? To show us that vagueness, subjectivity, and indeterminism, are not forced on us by experimental facts, but by deliberate theoretical choice?" (p. 160).
It seems clear that the Bohm formulation should be given much more attention when the problems that are widely taught as plaguing hidden-variable QM theories have already been overcome. A fuller overview of the Bohm interpretation of quantum mechanics can be found in the online Stanford Encyclopaedia of Philosophy at: http://plato.stanford.edu/entries/qm-bohm/