Image copyright © by Marcus Trahan

Particle Fever


Back in high school, when I was learning what little I know about particle physics (most of it probably wrong now, there were illustrations of what had happened at the business end of atom smashers, as we called them then. It was a burst of lines and curves, very pretty. And the experimenters could point at a short line and say, with confidence, “There! That is the track of a mu meson! It only exists outside the nucleus for a tiny fraction of a second! Isn’t that neat?” And I agreed it was, and decided I wanted to be a physicist. Then I battled with calculus, and lost, and decided to try something else.

That’s not how it works these days. This is an excellent documentary about the Large Hadron Collider, the biggest machine ever built by mankind. It is so big, seventeen miles in circumference, that it stretches beneath the border between France and Switzerland. And this ain’t some primitive brute like the giant bucket loaders that scrape coal from seams. Those seventeen miles contain super-conducting magnets, cooled by liquid helium, which is a real bitch to handle. It all has to be machined to insane tolerances, and kept squeaky clean. Just the computing power it takes to run the thing boggles the mind. It took ten years to build, and smashed its first hadron in 2008. And it captured the public’s imagination with talk of one of the primary reasons it was built, which was to find or disprove the so-called (by everyone but serious scientists, most of whom hated the term) “God particle,” the Higgs Boson. So we follow the progress of the development and first use of the collider. There is hope … and then disaster. A section of magnets ruptures, and takes about a year to get back on line. And then … success! We have found the Higgs Boson!

… or have we? It’s all too complex to explain, but basically, we can’t actually see a track of the particle. We have to analyze massive amounts of data, and then plot it on a curve with a statistical formula. If the high point of the curve has one value, the existence seems to be confirmed. If another value … well, I don’t pretend to understand it all, or even most of it, but I got the feeling that there is still room for doubt. Meanwhile, they seem to have discovered even more mysterious things, called pentaquarks. (Don’t even ask, I have no idea.)

It’s a fascinating show to watch, even if you only understand every fifth word. The LHC is currently (10/25/15) shut down undergoing an upgrade to its theoretical upper limit of energy, something like twice the already scary energies achieved. There are those who say they might produce a black hole down there under Switzerland, which would gobble up the Earth. It’s not something I can worry about too much. We would never know.

I am struck by how many women are involved in this project, at the highest levels. The person in charge of one of the four major experiments is a woman, and one of the chief engineers charged with keeping it running is also female. Now, it could be that the director cherry-picked these women to follow around, but when you look at the large audiences for the historic events we see, the sexes are about evenly divided. That sure wouldn’t have been the case when my high school textbook was being written.