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Politics, Morality, and Misrepresentation in Physical Science

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Politics, Morality, and Misrepresentation in Physical Science Politics, Morality, Innovation, and Misrepresentation in Physical Science and Technology Jed Z. Buchwald Physics in Perspective ISSN 1422-6944 Phys. Perspect. DOI 10.1007/s00016-016-0187-y 1 23 Your article is protected by copyright and all rights are held exclusively by Springer International Publishing. This e-offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com”. 1 23 Author's personal copy Phys. Perspect. Ó 2016 Springer International Publishing DOI 10.1007/s00016-016-0187-y Physics in Perspective Politics, Morality, Innovation, and Misrepresentation in Physical Science and Technology Jed Z. Buchwald* The pressures of politics, the desire to be first in innovation, moral convictions, and the potential dangers of error are all factors that have long been at work in the history of science and technology. Every so often, the need to reach a result may require leaving out a few steps here and there. Historians think and argue best through stories, so what follows are several tales, each of which exemplifies one or more of these aspects, though some reach back nearly two hundred years. The first concerns the depletion of the ozone layer; the second involves the discovery of electric waves by Heinrich Hertz in 1888; the third concerns the controlled production of electromagnetic radiation by Guglielmo Marconi and John Ambrose Fleming in the early 1900s; the fourth portrays the circumstances surrounding Joseph von Fraunhofer’s discovery and use of the spectral lines in the 1810s; our final case involves a bitter controversy between the physicist Hermann von Helmholtz and the astronomer Friedrich Zo¨ llner in the 1890s. Key words: Paul Crutzen; Michael Faraday; John Ambrose Fleming; Joseph Fraunhofer; Hermann von Helmholtz; John Herschel; Heinrich Hertz; Guglielmo Marconi; Mario Molina; Henry Rowland; Friedrich Zo¨ llner. The Ozone Layer In 1995 an MIT chemist by the name of Mario Molina shared the Nobel Prize in chemistry for his work on the atmospheric reactions that produce the depletion of the ozone layer.1 Since they were first handed out at the beginning of the last century, the Nobel Prizes have been the gold standard by which scientists have judged success. When you win a Nobel, your work has been canonized by the priestly guardians of science, all of whom live in Sweden near the Valhalla of the old Nordic gods. With a few exceptions, one would not want to argue with the appropriateness of the awards handed out over the last century, though the losers might want to do so. One would certainly not gainsay the Prize awarded for the * Jed Z. Buchwald is the Doris and Henry Dreyfuss Professor of History at the California Institute of Technology. He has authored or co-authored five books, most recently Newton and the Origin of Civilization (Princeton, 2012) with Mordechai Feingold. Author's personal copy J. Z. Buchwald Phys. Perspect. superb chemistry developed by Molina. But the research that led to the award bears discussion because it holds an interesting and timely lesson. The background to this work goes back quite far, to 1879 in fact, when ozone in the upper atmosphere was first recognized. Soon thereafter, it was realized that ozone shields the surface of the Earth from ultraviolet radiation. When it was also discovered that ozone is substantially present only in an altitude range of fifteen to fifty kilometers, and that it exhibits patterns of annual variation, scientists began to investigate what sort of chemical processes might be involved. Then, in the 1930s, a new industrial development took place when it was found that chlorofluoro- carbons were an ideal refrigerant—these CFCs, as they were soon widely called, were non-toxic and non-reactive, and so seemed to be perfectly suited for wide- spread use in the rapidly growing world of commercial refrigeration. Although scientists noted quite early that CFCs could easily accumulate in the stratosphere, at the time this raised no alarms. In fact, the first public discussion of the possibility that human activity might compromise the ozone layer occurred only in the 1960s and then did not involve the effects of CFCs, but rather of the high altitude flights of the proposed supersonic transport (SST). This was one element (though cer- tainly not the only one) in the debates of the day that led the US Congress to stop funding for the SST. This set the stage for the three events that led to Molina’s Nobel, which he shared with Paul Crutzen and Sherwood Rowland: research in the early 1970s identified a sequence of chemical reactions by which CFCs could gradually deplete the ozone layer. Then, surprisingly late, in the mid-1980s the worsening devel- opment each spring since the mid-1970s of an ozone ‘‘hole’’ over the Antarctic was announced; this was followed by a highly organized effort to gain data that revealed, among other things, that the size of the Antarctic hole varied over the course of a year. And here we come to a surprising and significant point. The chemistry that had been proposed for ozone depletion, and for which the Nobel was granted, requires ultraviolet radiation, and the various models that were built using this chemistry had predicted about a 5% general depletion of the layer near the equator by the 1980s. But the ozone hole occurred at the Antarctic. Not only is ultraviolet radi- ation comparatively small at the poles, the depletion effect there was far greater than the meager 5% predicted for the equator. Clearly something was up. Com- peting speculations were proposed by different groups of scientists. Then, as often happens, new experimental data altered the discussion. In the late 1980s, the Antarctic Airborne Ozone Experiment produced what amounted to ‘‘smoking gun’’ evidence that chlorofluorocarbons were the culprit, after which efforts focused on the detailed chemistry involved. In 1987, the Montreal Protocol for eliminating the use of CFCs was signed, but only in 1994 was a widely accepted chemical process that could explain the full depletion cycle evolved. The process of elaborating the chemistry continued thereafter. Author's personal copy Politics, Morality, Innovation, and Misrepresentation Despite the failures of the original chemical system that had linked high atmospheric concentrations of CFCs to low concentrations of ozone, no chemist today thinks that the first theory was actually false; it was instead only incomplete, for the principal reactions singled out did remain part of the story. Moreover, the original chemistry had been instrumental in focusing the research community’s attention on CFCs. This holds a lesson for scientific research that goes beyond the overly simple notion that a theory just makes predictions that either fit the data or do not, and that, if the fit is bad, then the theory must be tossed out. On the contrary, here we see that the fit between theory and experiment was not only bad, it was pretty much the reverse of what it should have been. Nevertheless, research scientists had no workable alternative but to continue pushing the original chemistry until it had been sufficiently fine-tuned to accommodate observation. There are at least two lessons in this story, one scientific and the other political. The scientific lesson is this: good researchers are stubborn; they do not simply cave in when faced with discrepant data. The data may be complex, the connections between model and data even more so, so that when the foundations of a theory are otherwise firm it is not a good idea to discard it too quickly. This is all the more true when dealing with something like the atmosphere, for here scientists encounter the difficult question of whether large scales require different ways of thinking than do the small scales that had been dealt with until the middle of the twentieth century. After all, the atmosphere cannot be put into a tabletop device. But it can be modeled on a computer, and a very great deal of recent science, as well as engineering, is done with computer models either because of computa- tional complexity, scale, or both. This trend raises important questions about just what the relation between a model and a natural system might be, and how dis- crepancies between data and computational outcomes should be dealt with, particularly when the system in question cannot actually be manipulated. Not only can we not yet play around with the atmosphere, one hopes that we would not want to do so even if we could, given the possibility of disastrous consequences, which brings us to the moral and political lesson of the ozone episode. Morality and politics are not words that easily go together, and not because politicians are inherently untrustworthy, though most Americans think with good reason that they probably are. Politics is and always has been the art of persuading others to do what the politician wants done, and that for a complicated variety of reasons. Some of those reasons may even be moral, however unlikely that may seem. But most of them are, and must be, pragmatic, which does not mean that they are necessarily immoral. Pragmatism comes in at least two forms: the prag- matics of the moment, and the pragmatics of vision.
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