Conceptual Foundations Of Quantum Mechanics: Second Edition (Advanced Book Classics) (Paperback)

by Bernard D'Espagnat (Author) "Classical physics identified matter with particles and radiation with "waves"..." (more)
Key Phrases: definite graduation interval, nonideal measurements, mean value rule, New York, Nuovo Cimento, Further Reading (more...)

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Product Description
This book provides a detailed view of the conceptual foundations of quantum physics and a clear and comprehensive account of the fundamental physical implications of the quantum formalism. It deals with nonseparability, hidden variable theories, measurement theories, and several related problems. Mathematical arguments are presented with an emphasis on simple but representative cases. The conclusion incorporates a description of a set of relationships and concepts that could compose a legitimate view of the world.

About the Author
Bernard d'Espagnat received his Ph.D in Theoretical Physics from the Sorbonne. He was a Research Physicist at the French National Center for Scientific Research, at the Fermi National Accelerator Laboratory in Chicago, at the Niels Bohr Institute in Copenhagen and at CERN in Geneva. He joined the University of Paris where he was a Professor at both the Paris and Orsay campuses, becoming the Director of the Laboratoire de Physique Thorique et Particules Elmentaires, Orsay, in 1970.

Product Details

• Paperback: 352 pages
• Publisher: Westview Press; 2 edition (April 6, 1999)
• Language: English
• ISBN-10: 0738201049
• ISBN-13: 978-0738201047
• Product Dimensions: 9.3 x 6.1 x 0.7 inches
• Shipping Weight: 1.2 pounds (View shipping rates and policies)
• Average Customer Review: 5.0 out of 5 stars See all reviews (2 customer reviews)
• Amazon.com Sales Rank: #1,035,897 in Books (See Bestsellers in Books)

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5 of 6 people found the following review helpful:

5.0 out of 5 stars Building a Rigorous Ontology 101, September 24, 2008

By	J. Storey (Thornton, CO USA) - See all my reviews (REAL NAME)

This review is from: Conceptual Foundations of Quantum Mechanics (Hardcover)

Anyone, physicist or otherwise, who is at all interested in the broader philosophical implications of quantum mechanics should be required to read d'Espagnat's works. Why? Quite simply, d'Espagnat is one of pioneers in exploring the broader implications of modern physics, especially in the boundary domain where physics meets metaphysics.

His concept of "veiled" reality is particularly important to scientists, who seem to need some occasional reminding that empirical work, crucial as it is in understanding our physical universe, is nonetheless- by definition- incomplete; there is always a "beyond" which remains forever hidden -in principle- to direct study and observation. What should be appreciated from d'Espagnat's investigation, moreover, is that the foundations of quantum mechanics seem to POINT one to this observation, at least in the estimation of this distinguished expert in the field of quantum "entanglement".

Although science cannot define this ultimate "veiled" realm, the scientific method enables us to progressively uncover aspects of it by virtue of observed manifestations in the empirical world, as revealed in the physical laws of our universe and, perhaps, our mental states as well. The author thus promotes an ontological "dual-aspect" position, where mind and matter are equally fundamental and interdependent, and both aspects are derived from something deeper (indefinable) that is neither...
One is reminded of similar positions arrived at by other physicists interested in the foundations of QM, such as Wolfgang Pauli and David Bohm, to name a few.

This early book on quantum foundations lays out the basis for d'Espagnat's views on the limits of science, using arguments from QM to examine a variety of popular philosophical positions, which became the theme of many of d'Espagnat's later books. The latter were aimed at a broader, non-technical (but intellectually curious) audience. But even in this book for physicists, primarily, one can see d'Espagant develop his theme of "veiled" reality as he examines and criticizes various philosophical schools of thought (including those of physicists, such as Bohr and Einstein) from the standpoint of quantum foundations. As such, d'Espagnat's investigations into the world of the philosophy of physics is valuable, coming as it is from one who tackles the problems from the "inside-out", as it were, instead of looking at physics from the outside, as is the case with many philosophers of science. This doesn't necessarily mean a physicist is always "correct" speculating on general ontological matters,of course, but the value of working knowledge of a subject shouldn't be under-emphasized. I'm not sure about you, but if I want to see what is being said about the consequences of a particular discipline, the first place I head is to the experts in that discipline, and not so quickly to the outsiders looking in... :-) Yeah, philosophers-everybody loves 'em.

It should be mentioned d'Espagnat's investigation is no direct doorway to theism, such as is found in the popular world religions. It is a huge leap indeed to go from the possibility of cautiously allowing the possibility of meta-(aka "beyond"-) physics, to a fully-developed systematic theology full of non-empirical elements. One shouldn't use physics as any kind of support for such a leap, although many have tried. For that matter, the supposed "support" of physics for ANY elaborate metaphysical constructs, whether theistic or non-theistic, is equally dubious. In other words, ALL metaphysical speculations remain completely arbitrary. Once empiricism is removed as a criteria, obviously pure objectivity is impossible.
This tells us something important in metaphysical wanderings...if one is truly interested in building a (reasonable) metaphysics based on known science, one's results may seemingly turn out reasonable, but one should always keep in mind the arbitrary nature of the effort. As d'Espagnat reminds us, this entire enterprise is forever "veiled", and we'll only get some glimpses (although these can be progressive in principle). Hence, there's simply no room for dogmatism or evangelical zeal here. Popular philosophies and religions of the world, take note...

But there is another, even more restrictive implication here. If one is trying to construct a reasonable metaphysics (defined here as, extrapolating BEYOND current physics but nonetheless trying not to VIOLATE what is currently known), the empirical foundation one is building on dictates certain limits in itself. That is, one cannot freely construct any metaphysics which contradicts known physical laws. Most of the great world religions, as well as popular parapsychology and new-age sentiments, are in conflict here. You can't build a speculative worldview trying to extend current ideas in physics, then ignore the laws of physics after you've constructed your metaphysical edifice :-)

Of course, clever (devout) scientists and theologians have devised ways around this, carefully building quasi-religious worldviews that incorporate, or try to incorporate, what modern science has to offer. It is always possible to tweak a traditional religion or philosophy and make it more scientifically respectable... Such efforts might escape the criticism of scientists and stand as somewhat legitimate possibilities, but the metaphysical elements that need to be defined in such offerings look somewhat suspicious or unneeded from a strictly mechanical point of view. In addition, if these offerings try to appeal to traditional religious teachings, such as John Polkinghorne's attempt to modernize Christianity with current quantum mechanics, the result unfortunately bares little or no resemblance to the original religious milieu...

What d'Espagnat's work shows us, perhaps more than anything else, is the inherent inability -in principle- of humans transcending the limits of our methods. If this reminds you of the famous philosopher Immanuel Kant exploring the limits of rational thought, bingo... the difference is, d'Espagnat recognizes we can progressively explore this "veiled" realm through the scientific method. We'll never quite perceive it directly given our finite limitations, but at least there is indeed room for optimism. The scientific enterprise turns out to be a noble and fruitful enterprise after all.

Whatever the case, d'Espagnat's main idea, that we must posit a broader aspect of reality which science can only penetrate in a progressive manner, is hardly a controversial concept. This concept may bother some in science or philosophy who are hardcore realists, believing that science is actually dealing with "ultimate reality" directly. Rather naively, upon reflection, this view believes with remarkable confidence that the achievement of science ("for all practical purposes" [FAPP] as John Bell might say...) is an ability to minimize human perceptions and sensibilities in the construction of the methodology. d'Espagnat calls this "strong" objectivity, vs. "weak" objectivity, which sees a human side to all scientific explorations. He remarks, "Quantum mechanics introduced another point of view, which consists essentially that the aim of science is not to describe ultimate reality as it really is...rather, it is to make account of reality as it appears to us, accounting for the limitations of our own mind and our own sensibilities".
d'Espagnat's strong point, really, is precisely this ability to see in quantum foundations an emphatic lesson: we have indeed moved a long way from the naive, purely objective descriptions of Nature found in classical physics, where descriptions of phenomena could be made without reference to a human element in their construction. Alas, some current physicists perhaps remain misguided about this lesson, STILL viewing abstract mathematical descriptions through a quasi-classical lens. I.e., they may be- according to d'Espagnat- confusing mathematical constructions with "reality-in-itself". Einstein himself held this lofty Platonic view of mathematics, similar of course to some of the ancient Greeks; d'Espagnat labels this preception "Einsteinian Realism", aka "Mathematical Realism", aka "Pythagorism".

The hope of "strong realism", that scientific inquiry is actually dealing directly with reality-as-it-is, seems a little too optimistic for some of us, certainly not a bet I'd care to wager for, but that's a problem THAT crowd has to deal with, not us...(Amazon readers, you're with me on this, correct?...Er..Correct?? [insert dead space here]).

5/12/09 Addendum to above review:
I guess I should really add something here in view of d'Espagnat winning the lucrative 2009 Templeton Prize; organizers said his work in quantum physics "revealed a reality beyond science that spirituality and art could help to partly grasp". It's a curious state of affairs, d'Espagnat himself is cautious in his writings to avoid big metaphysical leaps, so I'm not sure what the organizers saw in his work that pertains directly to "spirituality", except in a broad sense...
Nonetheless, d'Espagnat himself says he agrees in principle with the aims of the Templeton Foundation, and I suppose his "veiled reality" could be construed as a vague permission to explore other avenues, so what the heck...pocket that 1 million pounds and head out of town quick...We should all be so lucky. As Amanda Gefter (Opinion columnist for New Scientist magazine) points out, "It would be nonsensical to paint [D'Espagnat's God] with the figure of a personal God or attribute to it specific concerns or commandments. The 'veiled reality', then, can in no way help Christians or Muslims or Jews or anyone else rationalize their specific beliefs. The Templeton Foundation - despite being headed up by John Templeton Jr, an evangelical Christian - claims to afford no bias to any particular religion, and by awarding their prize to d'Espagnat, I think they've proven that to be true. I happen to believe that drawing any spiritual conclusions from quantum mechanics is an unfounded leap in logic - but if someone out there in the world is willing to pay someone £1 million for pondering the nature of reality, that's a world I'm happy to live in."

As for various comments from the peanut gallery (scientists and otherwise)on the appropriateness of d'Espagnat's early work on quantum nonseparability (now generally labeled "entanglement") being rewarded by this organization, I was entertained by the gauntlet of opinions, both yay and nay. Some critics, usually hard-nosed reductionists such as the Dawkins anti-religion crowd, see the Templeton Foundation as a dubious organization from square one, with all this "spiritual" talk and what not. Par for the course there. Other critics question d'Espagnat's own views, saying the supposed "holism" shown in Bell's Inequalities doesn't necessarily lead to observations about a general "ignorance" of reality. Some even label d'Espagnat an "anti-realist", as if he were spouting a viewpoint antagonistic to realism. Some don't like the seemingly "open" way d'Espagnat's philosophy ends up. Everybody wants a more precise description of possible metaphysics, if somebody like d'Espagnat could just guide them...
These criticisms sometimes beg the question whether some commentators have thought through his ideas well...as far as "realism" goes, d'Espagnat probably wouldn't be happy being called an "anti-realist", since he accepts- like most physicists- that there is a world which exists independently of experience, observation, and measurement. As for preciseness when it comes to the borderline of metaphysics, this is impossible. Although one should note that any metaphysical speculation that tries to build upon "hints" from physics is limited in the options...you can't just postulate anything. Not to mention that d'Espagnat is proposing a "dual-aspect" ontology, not dependent on our sensibilities of space and time, which itself provides a few (speculative) directions, perhaps somewhat similar to David Bohm's "implicate" vs. "explicate" orders (see d'Espagnat's essay "'State of the Art' and Perspectives: Quantum Physics and the Ontological Problem" for his mature thinking on these ideas...).

Personally, I take a pragmatic view of the whole mess; it's a nice thing that d'Espagnat finally got some well-deserved public recognition for his pioneering work in quantum foundations. Many hard-nosed physicists may not like the idea that it was the Templeton Foundation that did the award, but then again, since these guys DIDN'T win and would have surely given a speech and taken the money if they had been nominated, I see some sour grapes here. Plus, it's not like any physics organizations came out and offered d'Espagnat any cash prizes for his work, so a pox on the physics crowd too :-).

5.0 out of 5 stars A classical in the philosophy of physics, October 18, 2007

By	B. C. Jantzen "physicist-turned-philosopher" (Pittsburgh, PA USA) - See all my reviews (REAL NAME)

D'Espagnat carefully presents a concise reconstruction of the theory of non-relativistic quantum mechanics in axiomatic form, as well as careful analyses of each of the major difficulties inherent in its interpretation. His discussions of the metaphysical and epistemological questions surrounding the theory have played a significant role in setting the terms and temrinology of current debates in the philosophy of physics. For anyone seeking a better grasp of the nature and implications of quantum theory, whether he be a philosopher or physicist, this book is an essential read. It is, by any reasonable account, a classic.