February 1998, “Law Without Law…Or Something Like That” This morning I read one of the papers you gave me last week (“Information is Inevitably Physical”) and was reminded of your interest in the idea that the laws of physics may not be written in stone once and for all…but instead may be contingent upon the particular details of the universe itself…and indeed may be evolutionary à la Peirce, Wheeler, Lee Smolin, etc. At least one version or other of this kind of thing has intrigued me for some time (essentially since meeting John Wheeler in 1985). It's been sort of a hidden hobby, somewhat connected with separating the wheat from the chaff in quantum mechanics. My personal writings on the subject are now pretty voluminous, though not yet tight enough in substance that I show them to too many: most are in the form of emails to colleagues such as you. Anyway, if you're interested, perhaps I'll compile a small compendium and send it your way when I get back from Tokyo March 15 – I'm travelling essentially every moment until then. May be this will help us open a dialog to pinpoint where some real progress might be made. In the meantime let me tip you off to another article on the subject that I ran across recently: S. S. Schweber: “The Metaphysics of Science at the End of a Heroic Age,” in Experimental Metaphysics , edited by R. S. Cohen, M. Horne, and J. Stachel (Kluwer, Dordrecht, 1997), pp. 171–198.
February 1998, “Law Without Law…Or Something Like That” This morning I read one of the papers you gave me last week (“Information is Inevitably Physical”) and was reminded of your interest in the idea that the laws of physics may not be written in stone once and for all…but instead may be contingent upon the particular details of the universe itself…and indeed may be evolutionary à la Peirce, Wheeler, Lee Smolin, etc. At least one version or other of this kind of thing has intrigued me for some time (essentially since meeting John Wheeler in 1985). It's been sort of a hidden hobby, somewhat connected with separating the wheat from the chaff in quantum mechanics. My personal writings on the subject are now pretty voluminous, though not yet tight enough in substance that I show them to too many: most are in the form of emails to colleagues such as you. Anyway, if you're interested, perhaps I'll compile a small compendium and send it your way when I get back from Tokyo March 15 – I'm travelling essentially every moment until then. May be this will help us open a dialog to pinpoint where some real progress might be made. In the meantime let me tip you off to another article on the subject that I ran across recently: S. S. Schweber: “The Metaphysics of Science at the End of a Heroic Age,” in Experimental Metaphysics , edited by R. S. Cohen, M. Horne, and J. Stachel (Kluwer, Dordrecht, 1997), pp. 171–198.
ENERAL philosophy claims to be the critical subject which lays down for all of us what we may be allowed to think, and yet it has played no part whatever in the great revolutions of human thought of the present century-those connected with relativity and the quantum theory. It might have been expected that the scientists would have been constantly consulting the philosophers as to the legitimacy of their various speculations, but nothing of the kind has happened. Since no one can dispense with some sort of metaphysic, each scientist has made one for himself, and no doubt they contain many crudities, but it would seem that a deep interest in metaphysic is a disadvantage rather than an advantage to the physicist-at least I have the impression that those of my friends who are most inclined to speculate on the ultimate things appear to be the ones whose scientific work is most hampered by doing so. Now I propose to risk a similar indiscretion. I want to embody in it the practical philosophy of a physicist, and I do not mean it as an attack on the pure philosophers, who are very reasonable people, only chargeable with the minor offence of not having made me want to read their books! I had better begin by stating shortly the ideas I intend to discuss. There is a notable contrast between the way we think about things and the way we think we ought to think about them.
On 25 March 1935, the Physical Review received a paper from Albert Einstein, Boris Podolsky, and Nathan Rosen, with the title “Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?” A few days later, on 30 March 1935, I was born. My life with Einstein was off to a promising start. Some would call it an inauspicious start. Abraham Pais, for example, says in his otherwise admirable biography of Einstein [1] that “the only part of this article that will ultimately survive, I believe, is this last phrase [ No reasonable definition of reality could be expected to permit this ], which so poignantly summarizes Einstein's views on quantum mechanics in his later years.” But today, in this centenary of the Einstein annus mirabilis, as the EPR paper and I both turn 70, it is, in fact, the most cited of all Einstein's papers [2]. The debate over its conceptual implications rages hotter than ever, and for the first time, practical (well, for the moment still gedanken practical) applications of the EPR effect have emerged in cryptography and in other areas of quantum information processing. Being only five weeks old, I was unprepared to pay attention to the article that appeared in the New York Times on 4 May 1935 under an elaborate set of headlines and subheads: And I was completely oblivious to the stern rebuke from Einstein himself, published three days later in the Times , which declared that “any information upon which the article … is based was given to you without my authority. It is my invariable practice to discuss scientific matters only in the appropriate forum and I deprecate advance publication of any announcement in regard to such matters in the secular press.” Apparently Podolsky had tipped off the Times to the article, which did not appear in the sacred press until the 15 May issue of Physical Review. It is not clear that Einstein ever forgave him, and I wish I had been old enough to send Podolsky a cross letter myself. Anyone growing up in America in the 1940s knew that the preeminent genius of our age, and perhaps of any other, lived in Princeton, New Jersey, had a predilection for baggy sweaters, and was always badly in need of a haircut—as far ahead of his time in dress and grooming as he was ahead in science during his 1905 annus mirabilis.
The two essays here published for the first time are separated by an interval of thirty-five years. The first and longer one was written shortly before my appointment as Max Planck's successor in Berlin, and a few months before the idea of what is now called wave mechanics began for a while to monopolise my whole interest; the second and shorter one dates from two years after my appointment as Professor Emeritus at the University of Vienna. The two are closely related in theme, and, of course, also connect with many ideas which I have publicly advocated in the intervening period. I do not know whether it is presumptuous of me to suppose that readers will be interested in ‘my’ view of the world. The critics, not myself, will decide on this. But a gesture of decorous modesty is usually in fact a disguise for arrogance. I should prefer not to be guilty of this. Anyway, the total (I have counted) is about twenty-eight to twenty-nine thousand words. Not an excessive size for a view of the world. There is one complaint which I shall not escape. Not a word is said here of acausality, wave mechanics, indeterminacy relations, complementarity, an expanding universe, continuous creation, etc. Why doesn't he talk about what he knows instead of trespassing on the professional philosopher's preserves? Ne sutor supra crepidam .
Spring 2005, whilst sitting at my desk in the physics department at Leeds University, marking yet more exam papers, I was interrupted by a phone call. Interruptions were not such a surprise at the time, a few weeks previously I had published an article on quantum theory in the popular science magazine, New Scientist, and had since been inundated with all sorts of calls from the public. Most callers were very enthusiastic, clearly demonstrating a healthy appetite for more information on this fascinating topic, albeit occasionally one or two either hadn’t read the article, or perhaps had read into it a little too much. Comments ranging from ‘Can quantum mechanics help prevent my hair loss?’ to someone telling me that they had met their twin brother in a parallel Universe, were par for the course, and I was getting a couple of such questions each day. At Oxford we used to have a board for the most creative questions, especially the ones that clearly demonstrated the person had grasped some of the principles very well, but had then taken them to an extreme, and often, unbeknown to them, had violated several other physical laws on the way. Such questions served to remind us of the responsibility we had in communicating science – to make it clear and approachable but yet to be pragmatic. As a colleague of mine often said – sometimes working with a little physics can be more dangerous than working with none at all. ‘Hello Professor Vedral, my name is Jon Spooner, I’m a theatre director and I am putting together a play on quantum theory’, said the voice as I picked up the phone. ‘I am weaving elements of quantum theory into the play and we want you as a consultant to verify whether we are interpreting it accurately’. Totally stunned for at least a good couple of seconds, I asked myself, ‘This guy is doing what?’ Had I misheard? A play on quantum theory? Anyway it occurred to me that there might be an appetite for something like this, given how successful the production of Copenhagen, a play by Michael Freyn, had been a few years back.
12 June 1999, “Interest in Pauli” I have come across a reference to a paper of yours that I have not been able to obtain. May I ask of you to send me a reprint of it? The paper is: C. P. Enz, “Wolfgang Pauli and the Role of the Observer in Modern Physics,” in Philosophy of the Natural Sciences: Proceedings of the 13th International Wittgenstein Symposium , edited by P. Weingartner and G. Schurz (Verlag Holder–Pichler–Temsky, Vienna, 1989), pp. 110–119. I have read several of your other papers on Pauli's thought and have been uniformly pleased with each. I am especially interested in his ideas concerning the demise of the “detached-observer” notion within quantum theory. (I would also be interested in any of your other works on the subject that may have been written since your 1992 article, “Wolfgang Pauli between Quantum Reality and the Royal Path of Dreams.” This is the latest one that I am aware of.) About myself, I am a theoretical physicist at Caltech who specializes in quantum information theory and quantum computing. I am well acquainted with your colleague Nicolas Gisin at the University of Geneva. 21 August 1999, “One More Article?” Upon my return from Cambridge a couple of weeks ago, I found in my mailbox your package full of wonderful papers! Thank you so much.