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In Praise of Praise: How Historians Could Improve Celebratory History May 10, 2013

Posted by Will Thomas in Commentary Track.
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This afternoon, thanks to the initiative of Jim Grozier, I am giving a talk at the weekly High Energy Physics seminar at UCL.  The subject will be my work on experimentation in early particle physics.  While my “Strategies of Detection” paper mainly concerns the problem of how to build “mesoscopic” histories of experimental practices, my talk will repurpose my argument to discuss how we can articulate and evaluate experimental ingenuity and skill.  This jibes with other thoughts I’ve had about whether it could ever be considered legitimate for a professional historian to write a celebratory narrative of scientific progress.  The very notion triggers the raising of well-disciplined eyebrows: isn’t it the job of professional historians to problematize celebratory narratives?  But, really, I can’t think of a good reason why not, and it seems to me there is substantial opportunity to improve the genre.


Historical Scientific Standards, or: The Career of the “Varytron” April 14, 2013

Posted by Will Thomas in Commentary Track.
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Alichanian, apparatus

While Robert Millikan thought, circa 1930, that signs of the synthesis of the elements could be gleaned from the energy spectrum of the cosmic radiation, in the late 1940s Armenian physicists (and brothers) Artem Alikhanian and Abraham Alikhanov thought that the way forward in the nascent field of particle physics was by measuring the cosmic radiation’s mass spectrum. It turned out that they were right that unknown particles existed within that spectrum, but wrong that measuring that spectrum was the best path to take to stake discovery claims to them.

Alikhanian and Alikhanov’s work on cosmic radiation dates—remarkably, given that they were Soviet—to World War II, when, like Italians working at the same time (Monaldi, “Life of µ”), they used counter devices to measure the radiation’s properties. In the early postwar years, they (with a third reseracher, A. Weissenberg, on whom I have found little information) assembled counters in tiers (diagram at right*) so that they could make a rough measurement of the deflection of particles in a magnetic field, and make estimates of particle mass. Doing so, they measured a large number of particle masses, which, they argued, were much heavier than the known meson (or “mesotron”, now known as the muon, or µ), and yet lighter than the proton. Because these new particles seemed to have a variety of masses, Alikhanian and Alikhanov gave them the unitary name, “varytron”.

Subsequently, using a larger magnetic field, Alikhanian and Alikhanov were able to resolve the spectrum of varytron masses into discrete clusters, ostensibly representing individual particles. Working high in the Armenian mountains, previously unacknowledged particles, especially pions, probably were passing through their apparatus. However, in those days, when particle physics began to emerge from nuclear physics and cosmic-ray studies, not only were the brothers never credited with the discovery of any new particles, this work seems to have had very little influence at all. To understand why, we need to attend to the intricacies of the sorts of scientific arguments that prevailed at that time—the sort of task I emphasized in my recent series on history-philosophy relations.