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One of the professors at my university is a theorist, and a good one; and he had an idea. He thought that a certain kind of process might be interestingly sensitive to New Physics, the grail for which all particle physicists are searching.

An aside here : Particle physics is, in a sense, in the business of putting itself out of business. If we ever do find a Theory of Everything which accounts for all particle interactions, at all energy scales, and right back to the Big Bang - then the rest is just applications, which any mere nuclear physicist can do. But that applies to the science as a whole. Each individual particle physicist, of course, has to hope that he will be gainfully employed throughout his life, in the field he has chosen. So in the generic sense, we might wish to understand everything; but at the personal level, we have to add "But not too soon!" Hence the search for New Physics - and the capitals are quite seriously meant.

This professor, then - let's call him Dr. Smith - believed he was on to something interesting. Now, the way to look for New Physics in a process is to first calculate it using the physics you know, then measure it, and see if the two agree. If not, you may have found something. So Dr. Smith, being a theorist, calculated the process - using quark operator expansion methods that I find, in all honesty, esoteric - and presented his results, including some hypothetical ones for this, that, and the next kind of New Physics, in various places. I was at one such seminar, in fact, which is how I know what methods he used. Not that I understood them.

The next step, then, was to measure the process, which is where my supervisor - let's call him Dr. Jones - comes in. (It was he who roped me into going to that seminar. If given a choice, I stay away from the weird theoretical stuff.) "Jones", quoth Dr. Smith, "this process should be measurable in the initial-state-radiation events at BaBar. Do you think your detector is good enough to find them?" (I paraphrase from memory, but I believe I am close to the words uttered.) "Well," said Dr. Jones, "I don't know. But it would certainly be interesting to have a look."

So he went off to his lair to do some hacking. (Oddly enough, he didn't assign it to me, though this sort of rough first-pass programming is what grad students are for. Perhaps he was worried about me passing my Quals.) A few days later, I chanced to be in his office on some other business as Dr. Smith came by to ask about the results. And Dr. Jones had to report, "Well, here's the ISR electron spectrum. A nice power curve, just as you'd expect. And here, in the region where your process would create a bump - there are a few extra events. Maybe five. Which could easily be a random fluctuation - it's a one-sigma effect. Sorry, but there just isn't enough data here to tell one way or the other. Our particle identification isn't good enough in this energy regime. And the muon spectrum is even worse, they're very difficult to tell from pions so there's more noise. Maybe in two years, when we'll have doubled our data set. As it is, I could set an upper bound, but I can't get a measurement. Sorry." And Dr. Smith said, and I quote. "Oh. Damn." And he left muttering under his breath, clearly quite disappointed. I felt sorry for him, and a bit disappointed myself. It would have been quite exciting to be this close to a genuine possibility of New Physics.

So I wonder. In two years, when we'll have doubled our data set - using the nice new LST detectors in the flux return, instead of the rather tired RPCs, at that - what will Dr. Smith be doing? Will he even remember his idea of two years ago? And if not - how long until someone thinks of it again? The field of particle physics isn't that big. Have we missed an excellent insight into something genuinely new, because someone though of it a bit too early? And if we have - how often does that happen? What might we know today, if only ideas were synchronised with the equipment to act on them?

A chance sequence of events, not very important in the grand scheme of things. But it made me think. And I feel rather proud to have been in a position to witness it. Even if this time, the answer was a negative one - who knows? Perhaps next time I'll be there to see physics history being made.

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