Favorite prefaces – I
This is the first of a series of posts with short excerpts of prefaces/introductions of books that I find interesting or curious. This is just for fun, but hopefully will lead to a collection of memorable sentences or ideas that compels us further on the subject.
PCT, Spin and Statistics, and All That
by Raymond F. Streater and Arthur S. Wightman
In the beginning, when Dirac, Jordan, Heisenberg, and Pauli created the quantum theory of fields, it was not expected that it would provide a consistent description of Nature. After all, it was only a quantized version of the classical theory of Maxwell and Lorentz, a theory which was well known to be afflicted with diseases arising from the infinite electromagnetic inertia of point particles. Many physicists were of the opinion that any project to make the theory’s mathematical foundation more rigorous was probably ill-advised; first the classical foundation should be set right. Such alterations might so change the basis of the theory that a mathematically rigorous discussion of any preceding version would be entirely irrelevant. More recently, it has been suggested that the trouble is that the theory is too modest; it is not designed to predict the masses of the elementary particles or the values of the coupling constants, and should be fundamentally changed with this in view.
However, attempts to go beyond the theory foundered again and again. What successes were achieved were either phenomenological, or were due to systematic developments of the original formalism. But the quantum theory of fields never reached a stage where one could say with confidence that it was free from internal contradictions–nor the converse. In fact, the Main Problem of quantum field theory turned out to be to kill it or cure it: either to show that the idealizations involved in the fundamental notions of the theory (relativistic invariance, quantum mechanics, local fields, etc.) are incompatible in some physical sense, or to recast the theory in such a form that it provides a practical language for the description of elementary particle dynamics.
The last ten years have seen a number of attempts to meet the situation head on. (The physicists who have engaged in this kind of work are sometimes dubbed the Feldverein. Cynical observers have compared them to the Shakers, a religious sect of New England who built solid barns and led celibate lives, a non-scientific equivalent of proving rigorous theorems and calculating no cross sections.) These efforts have not yet led to a solution of the Main Problem, but they have yielded a number of by-products, very general insights into the structure of a field theory. The present book is devoted to an exposition of some of these general results, the physical ideas they embody, and the mathematics necessary for their proofs.
February 7, 2009 at 6:25 am
Hi Christine,
The complaint lodged by the author’s of your quote is certainly not a new one, yet rather a persistent one in science in general and physics more particularly. My personal take on it is it dates back to the differences in the methodology of science that where drawn between Bacon and Descartes. With Bacon it was inductive reasoning that was paramount in terms of scientific discovery, while for Descartes it was the deductive process insisted to be key; with the inductive only serving to strengthen the validity of the premise(s).
With Bacon, whose first champion was Newton, phenomenology served to indicate the laws, while with Descartes, whose greatest champion was Einstein insisted the reason of nature formed laws that demanded (forced) the phenomenology one finds. This debate still rages as to which shall proven as true. Which ever it turns out to be it is only hoped by me that the one thing on which both methodologies agree be maintained, which is that nature itself by way of observation and experiment should decide. Although I have to admit that I would like to find that Descartes’ limit as what forms reality be found as ultimately true, I’ve always liked the vision of promise that Bacon held out for the ability and utility of science, when he said in his “Novum Organum” (New Instrument)the following:
“But if there be any man who, not content to rest in and use the knowledge which has already been discovered, aspires to penetrate further; to overcome, not an adversary in argument, but nature in action; to seek, not pretty and probable conjectures, but certain and demonstrable knowledge — I invite all such to join themselves, as true sons of knowledge, with me, that passing by the outer courts of nature, which numbers have trodden, we may find a way at length into her inner chambers.”
Best,
Phil