Science After Sunclipse

The story so far: New Scientist magazine publishes an issue with a heartbreakingly sensationalist cover, and biology experts across the Blogohedron get up in arms. (See Sandwalk, Ecographica, Evolutionary Novelties and Genomicron for sample critiques of both cover and content.) Notorious evilutionary superscientist P-Zed points out that this editorial inside the magazine is significantly more sensible than the glossy outer shell. I start to read it, and before I get through a paragraph, my palm and my forehead suffer an impact event.

"THERE is nothing new to be discovered in physics." So said Lord Kelvin in 1900, shortly before the intellectual firestorm ignited by relativity and quantum mechanics proved him comprehensively wrong.

Ahem. When did one old man's grumpiness become the definitive statement about a scientific age? What about Kelvin's contemporaries, who had a better idea of what was going on? If you're trying to foster an understanding of how change happens in science, what's the point of regurgitating these tired one-liners — aren't you the slightest bit worried that your readers will come away with the wrong impression? You know, "Everyone thought their problems were all wrapped up. Lord Kelvin even said so! But then everything they thought turned out to be wrong. ZOMG!"

(To which the sequel often is, "Maybe those arrogant scientists need to be taken down a peg", followed by "Maybe Darwin was all wrong, too", and so forth.)

If one wants to make an informative and useful analogy between the way physics changed after Kelvin's day and the way modern biology differs from what Darwin knew (or what Rosalind Franklin knew, or whatever), then one has to get the state of affairs in Kelvin's time right. Even if the desired goal is merely to illustrate the folly of scientific hubris — to show that one grumpy old man can indeed be wrong — this is not worth distorting history.

One classic illustration of how Kelvin's contemporaries knew their understanding of physics was incomplete involves the specific heats of gases. How much does a gas warm up when a given amount of energy is poured into it? The physics of the 1890s was unable to resolve this problem. The solution, achieved in the next century, required quantum mechanics, but the problem was far from unknown in the years before 1900. Quoting Richard Feynman's Lectures on Physics (1964), volume 1, chapter 40, with hyperlinks added by me:

The first great paper on the dynamical theory of gases was by Maxwell in 1859. On the basis of ideas we have been discussing, he was able accurately to explain a great many known relations, such as Boyle's law, the diffusion theory, the viscosity of gases, and things we shall talk about in the next chapter. He listed all these great successes in a final summary, and at the end he said, "Finally, by establishing a necessary relation between the motions of translation and rotation (he is talking about the 1/2 kT theorem) of all particles not spherical, we proved that a system of such particles could not possibly satisfy the known relation between the two specific heats." He is referring to γ (which we shall see later is related to two ways of measuring specific heat), and he says we know we cannot get the right answer.

Two years later, in a lecture, he said, "I have now put before you what I consider to be the greatest difficulty yet encountered by the molecular theory." These words represent the first discovery that the laws of classical physics were wrong. This was the first indication that there was something fundamentally impossible, because a rigorously proved theorem did not agree with experiment. About 1890, Jeans was to talk about this puzzle again. One often hears it said that the physicists at the latter part of the nineteenth century thought they knew all the significant physical laws and that all they had to do was to calculate more decimal places. Someone may have said that once, and others copied it. But a thorough reading of the literature of the time shows they were all worrying about something.

When the first paragraph of the editorial chews on the textbook cardboard, my hopes are not raised for the rest. Johnson and Horgan assure us that science journalism can set research in its proper context, but when the history lessons handed to us are gross oversimplifications which leave out all the interesting parts of the story, how much insight can we honestly hope for?