Friday, April 14, 2017

Machine Envy

Whenever I visit scientists to discuss their research, there comes a moment when they say, with barely concealed pride: ‘Do you want a tour of the lab?’ It is invariably slightly touching — like Willy Wonka dying to show off his chocolate factory. I’m glad to accept, knowing what lies in store: shelves lined with bottles or reagents; gleaming, quartz-windowed cryogenic chambers; slabs of perforated steel holding lasers and lenses.

It’s rarely less than impressive. Even if the kit is off-the-shelf, it is wired into a makeshift salmagundi of wires, tubes, cladding, computer-controlled valves and rotors and components with more mysterious functions. Much of the gear, however, is likely to be homemade: custom-built for the research at hand. Whatever else it might accomplish, the typical modern lab set-up is a masterpiece of impromptu engineering — you’d need degrees in electronics and mechanics just to put it all together, never mind making sense of the graphs and numbers it produces. And like the best engineering, these set-ups tend to be kept out of sight. Headlines announcing ‘Scientists have found…’ rarely bother to tell you how the discoveries were made.

Would you care? The tools of science are so specialised that we accept them as a kind of occult machinery for producing knowledge. We figure that they must know how it all works. Likewise, histories of science focus on ideas rather than methods — for the most part, readers just want to know what the discoveries were. Even so, most historians these days recognise that the relationship between scientists and their instruments is an essential part of the story. It isn’t simply that the science is dependent on the devices; the devices actually determine what is known. You explore the things that you have the means to explore, planning your questions accordingly.

When a new instrument comes along, new vistas open up. The telescope and microscope, for example, stimulated discovery by superpowering human perception. Such developments prompt scientists to look at their own machines with fresh eyes. It’s not fanciful to see some of the same anxieties that are found in human relations. Can you be trusted? What are you trying to tell me? You’ve changed my life! Look, isn’t she beautiful? I’m bored with you, you don’t tell me anything new any more. Sorry, I’m swapping you for a newer model… We might even speak of interactions between scientists and their instruments that are healthy or dysfunctional. But how do we tell one from the other?

It seems to me that the most effective (not to mention elegant) scientific instruments serve not only as superpowers for the senses but as prostheses for the mind. They are the physical embodiments of particular thoughts. Take the work of the New Zealand physicist Ernest Rutherford, perhaps the finest experimental scientist of the 20th century. It was at a humble benchtop with cheap, improvised equipment that he discovered the structure of the atom, then proceeded to split it. Rather than being limited by someone else’s view of what one needed to know, Rutherford devised an apparatus to tell him precisely what he wanted to find out. His experiments emerged organically from his ideas: they almost seem like theories constructed out of glass and metal foil.

In one of his finest moments, at Manchester University in 1908, Rutherford and his colleagues figured out that the alpha particles spewed out during radioactive decay were the nuclei of helium atoms. The natural way to test the hypothesis is to collect the particles and see if they behave like helium. Rutherford ordered his glassblower, Otto Baumbach, to make a glass capillary tube with extraordinarily thin walls such that the alpha particles emitted from radium could pass right through. Once the particles had accumulated in an outer chamber, Rutherford connected up the apparatus to become a gas-discharge tube. As electrodes converted the atoms in the gas into charged ions, they would emit light at a wavelength that depended on their chemical identity. Thus he revealed the trapped alpha particles to be helium, disclosed by the signature wavelength of their glow. It was an exceedingly rare example of a piece of apparatus that answers a well-defined question — are alpha particles helium? — with a simple yes/no answer, almost literally by whether a light switches on or not. (...)

Today, however, they have become symbols of prestige as never before. I have several times been invited to admire the most state-of-the-art device in a laboratory purely for its own sake, as though I was being shown a Lamborghini. Stuart Blume, a historian of medical technology of the University of Amsterdam, has argued that the latest equipment serves as a token of institutional might, a piece of window-dressing to enhance one’s competitive position in the quasi-marketplace of scientific ideas. I recently interviewed several chemists about their use of second-hand equipment, often acquired from the scientific equivalents of eBay. Strangely, they all asked to remain anonymous, as though their thrift would mark them out as second-rate scientists.

One of the dysfunctional consequences of this sort of attitude is that the machine becomes its own justification, its own measure of worth. Results seem ‘important’ not because of what they tell us but because of how they were obtained. Despite its initial myopia, the Hubble Space Telescope is one of the most glorious instruments ever made, a genuinely new window on the universe. Even so, when it first began to send back images of the cosmos in the mid-1990s, Nature was plagued with content-free submissions reporting the first ‘Hubble image’ of this or that astrophysical object. Authors were often affronted to hear that the journal wanted, not the latest pretty picture, but some insight into the process it was depicting.

At least this kind of instrument-worship is relatively harmless in the long run. More problematic is the notion of an instrument as a ‘knowledge machine’, a contraption that will churn out new understanding as long as you keep cranking the handle.

by Phillip Ball, Aeon |  Read more:
Image: Gregg Segal/Gallery Stock