While working on my series of essays on quantum mechanics over the last couple of months, I was also reading some books related to other areas of physics. In my next couple of postings, I would like to discuss these books.
The first book I would like to discuss is an older one, published in 1984. It is entitled Constructing Quarks: A Sociological History of Particle Physics and written by Andrew Pickering. I introduced quarks and other particles of matter back on March 18 and March 26, 2005.
The main idea of Pickering's book is that, contrary to the image many may hold of science where conclusions about which theories to support are based on self-evident, objective findings of experiments, in actuality a lot of subjectivity goes into scientific judgments. I, myself, am a social scientist, so the study of how ideas become popular or unpopular had some appeal to me. It turns out, however, that the book's 400-plus pages contain quite a lot of technical physics, with some sociology sporadically inserted.
One example of Pickering's thesis about subjectivity involves acceptance of the "standard model of electroweak interactions" over possible alternatives (click here for the Wikipedia's coverage of the electroweak model, and here for my earlier discussion of the forces of nature, including the electromagnetic and weak forces). Pickering argues that:
In retrospect, it is easy to gloss the triumph of the standard model in the idiom of the 'scientist's account': the Weinberg-Salam model... made predictions which were verified by the facts. But missing from this gloss, as usual, is the element of choice. In assenting to the validity of the standard model, particle physicists chose to accept certain experimental reports and to reject others. This element of choice was most conspicuous in the communal change of heart over the Washington-Oxford atomic-physics experiments... ...in 1977 many physicists were prepared to accept the null-results of the Washington and Oxford experiments and to construct new electroweak models to explain them. We also saw that by 1979 attitudes had hardened. In the wake of Experiment E122, the Washington-Oxford results had come to be regarded as unreliable. In analysing this sequence, it is important to recognise that between 1977 and 1979 there had been no intrinsic change in the status of the Washington-Oxford experiments. No data were withdrawn, and no fatal flaws in the experimental practice of either group had been proposed. What had changed was the context within which the data were assessed... (p. 301).
In another episode, regarding "charmed" quarks, Pickering writes that:
It was no coincidence that the charm explanation of the new particles triumphed... The charm explanation sustained a multifaceted symbiosis of practice, wherein gauge theorists, hadron spectroscopists and experimenters in a whole range of traditions could draw upon one another's research for justification and subject matter for future practice... By 1976, charm was central to such a range of practice that arguments could always be marshalled in favour of seeing misfits between prediction and data as important results rather than as serious problems. That, for example, the hidden-charm [Greek letter symbols that I can't show] particles first appeared at the wrong masses and then disappeared caused few doubts, if any, over the validity of charm. Such discrepant phenomena were simply seen to call for further theoretical and experimental work, which would itself command the attention of a wide audience. Alternative models of the new particles did not inspire such dynamic acquiescence... (p. 272).
Thomas Kuhn is a major figure in the dynamics of scientific trends. His ideas are discussed as follows in a Caltech paper on "How Science Works" (p. 6):
A paradigm, for Kuhn, is a sort of consensual world view within which scientists work. It comprises an agreed upon set of assumptions, methods, language, and everything else needed to do science. Within a given paradigm, scientists make steady, incremental progress, doing what Kuhn calls “normal science.”
As time goes on, difficulties and contradictions arise that cannot be resolved, but one way or another, they are swept under the rug, rather than being allowed to threaten the central paradigm. However, at a certain point, enough of these difficulties have accumulated so that the situation becomes intolerable. At that point, a scientific revolution occurs, shattering the paradigm and replacing it with an entirely new one.