Saturday, September 24, 2011

Hot Neutrinos and Embarrassing Science Reporting

For years, cellular biologists have been telling us that it is basically impossible for humans to live more than 115 years. But this week, a man died at the age of 115 years, one day — a day over this theoretical age limit. In the news media, scientists debated the significance of this event. “This raises the very real possibility that we can live forever,” some said. “We’ll be able to get younger just as easily as we get older.” But others wondered about the degree of certainty surrounding the man’s exact time of birth, and cast doubt on other aspects of the story. Most top scientists, when reached, simply refused to comment, not wanting to risk saying anything at all about such a sensational story.

That’s not a true story. I made it up just now. But it gives you an idea of how far off scientists and journalists were when they responded to a major scientific event that did take place this week.

The actual story had to do with neutrinos. Nuclear scientists recorded neutrinos traveling from Switzerland to Italy faster than anyone would have thought possible. Neutrinos are tiny, lightweight particles that speed through solid objects the same way they stream through empty space. In this experiment, neutrinos went right through the rocks that lie under the Italian Alps. They arrived at a laboratory in Italy 60 nanoseconds early. That is, according to all our current theories, they went a tiny bit faster than light would take to travel the distance we think is involved.

The catch is, and this is where it becomes embarrassing, the way we know about distance is by measuring it using light. But light can’t travel through solid rocks, so the distance involved is only theoretical. It is fair enough for headlines to blare about neutrinos that moved “faster than light,” if the stories themselves had clarified that the “light” involved was only theoretical.

But there was no mention of this. Instead, journalists quoted physicists going on about the possibility of repealing the Special Theory of Relativity that originally established the speed of light as a universal constant. If neutrinos could go from Switzerland to Italy, then we could travel across the universe in the blink of an eye. We would soon be traveling backward in time. Everything that was impossible would now be possible. Other reporting, shamefully, set out to debunk the findings, as if the world’s top nuclear scientists were suddenly high school physics students who couldn’t read a ruler accurately.

The actual significance of the unexpectedly fast neutrinos is not as sensational as what you will read in the New York Times, but the implications are no less disturbing. The simplest explanation is that space and time are not as simple and linear as we imagine. We know that space and time are distorted by stars and black holes. Supposedly nothing on Earth is massive enough to disturb our comfortable assumption of flat Euclidean space or fast enough to prevent time from being measured in a simple linear fashion by carefully synchronized clocks. But this result raises the possibility that right under our feet, space and time are not so flat as we have imagined. Another possibility, nearly as disturbing, is that some kind of spooky quantum weirdness that occurs when neutrinos move through rocks allows them to hop from point to point far more often than we ever could have imagined. The actual explanation might be something more fantastic than either of these, but it makes sense to start with the obvious explanations before resorting to something off the wall.

Or, for that matter, before repealing the physical laws of the universe. It bears repeating that we use light to measure distance, so any distance computed in the absence of light is only a theory. You cannot use one theory to repeal another theory. Rather, in hard science, theories are taken away only by contrary observations. It is distressing and embarrassing to see how eager even respected scientific news outlets and experienced scientists have been to abandon hard science when confronted by strange behavior from neutrinos. But when something unexpected has been seen, that is when a scientific approach is needed more than ever.