Tuesday, December 13, 2011

On Stupid Names and Poorly-Understood Statistics

Let's get one thing right out of the way: the "God particle" is a stupid, nearly nonsensical name for it. It's called the Higgs boson, and that's all I'm going to say about stupid names.

You may have noticed the Higgs boson in the news the last few days, since a couple teams at CERN have announced growing evidence, though not yet "definitive proof," that the particle exists. Physicists believe that the Higgs particle is, long story short, responsible for things having mass — that is, weighing something other than zero. It would be a big deal indeed if they had definitive proof of its existence.

Trouble is, there is no such thing as definitive proof. You should understand why that's so, because knowing why make you wiser. Wiser, that is, about people trying to manipulate your beliefs about science.

Why can't there be definitive proof? No matter how hard you try, you can't do an infinite number of measurements, consider all the other possibilities, and generally be omniscient. What you can do is be really, really confident, and the more evidence you have, the more confident you can be. Thus, a few years from now when someone inevitably claims there is definitive proof of the Higgs's existence, what that really means is that physicists are really, really confident that it exists. Scientists are fairly confident now, but as the evidence grows, so will the confidence.

Now, why am I ranting about this? Because the idea that definitive proof could exist is a nefarious one. If a scientist admits that there isn't definitive proof of an idea, others will sometimes deride it as "just a theory."  That's a red herring — some theories are right, and some are wrong. By collecting more and more data to test a theory, we can be more confident about whether the theory is right or wrong.

Probably this isn't a big deal for the Higgs, but there are times when this seemingly minor point takes on political baggage — climate change and evolution come to mind. If you hear a politician saying there's no definitive proof of this or that, well, now you know better. The right question isn't whether there's definitive proof — there isn't. The right question is how confident we should be. On climate change and evolution, scientists are quite confident.

As for the Higgs, we'll have to wait and see.