Tales of the unexpected

I’ve spent the last couple of days at a meeting of the STFC Projects Peer Review Panel (PPRP). We evaluate all of the large project proposals (big telescopes, satellites, detectors for particle and nuclear physics) that are submitted to the funding council. Despite the still-unresolved crisis in STFC funding, projects are still being proposed, and some of them even funded. It was eye-opening being on the other side of the table for a change — although I can’t really talk about what we saw.

But the best part of the two days was the following quote which appeared on one of the slides:

“…and unexpected systematic errors are to be expected.”

The beauty of this apparently paradoxical statement is that it’s true: no matter how clever we are in understanding our apparatus, experiments never quite work exactly as we predict, and the hardest part is trying to understand exactly how it’s gone wrong. Are those extra counts in our detector from cosmic rays? A badly-soldered connection? Interference from television? Or does it turn out to be a Nobel-prize-winning discovery of a cosmic background?