PHYSICS and astronomy have always enjoyed a certain reverence among the sciences. They deal with crisp certainties, expressed as mathematical formulae that appear to leave no room for error.
But these days, physicists aren’t quite so sure of themselves. Today’s experiments designed to extend our understanding of the cosmos deal with wisps and ghosts. Often the evidence is so slender it can be easy to miss – or misinterpret. Stars flickering into existence at the dawn of the universe are so far away that their light is barely perceptible. And some particles interact so rarely that even the best detectors spot only a tiny fraction of them. The boldest claims about the universe rely on physicists sifting the truth from the millions of measurements they make.
Now physicists are starting to acknowledge that they have a lot to learn about handling uncertainties in their data. And they are getting help from a seemingly unlikely source: biologists and medical researchers, who deal with uncertainty all the time.
“For a billion dollars, we build fantastic telescopes with quantum-perfect detectors,” says Eric Feigelson, an astronomer at Pennsylvania State University in Philadelphia. “We use the best physical models we can, the best computers for processing data. We’d never be sloppy in classifying a star. But there’s one link in this steel chain that is made of paper: the one where we interpret the data using mathematics that’s 100 years old.”
Physicists like Feigelson are beginning to realise that instead of being a bane, uncertainty brings with it the potential for discovery. But to continue expanding our understanding of the cosmos they are going to have…
