Crime Scene Investigation

I recently talked to a friend who is all into crime novels and he continues to recommend books despite my obvious disinterest. I keep telling him I'm not much into whodunits, yawn, I spend my whole day investigating suspects and trying to figure out why they disagree and what the real story is. True, the suspects are the assumptions I've used and not the gardener and the wife's lover, but anyway. Then he goes on, yesyes, but did you read...?

Then I coincidentally came across an article titled "Even Scientist's Can't Decide". The crime committed in this title is the word 'even'. What it signals to me is that scientists are expected to present unchangeable facts. Fundamental truths. Possibly it has been the case for centuries that indeed when scientific research reached the public it was the already well established knowledge. Scientists have found. And what the scientists say is not to doubt. Reliable. Does not change from one day to the next. At least not generally. And if it does we call it a revolution and put it on the front page.

What is the image of the scientist that is distributed in the media today? A white haired man in a lab coat explaining you'll be happy for the rest of your life if you only eat two apples a day and brush your teeth three times, at least two minutes. And don't forget to floss. And btw, of course you shouldn't just take any toothpaste, but dentists recommend. Clinically proven. Trust him. He's a scientist. I encourage you to do a Google image search for 'scientist' - tells you all you need to know.

But look now, what ever happened to science? Nowadays, even the scientists can't decide! What is the world coming to! We can as well go back to superstition or religion. At least then we have fundamental truths. Unchangeable facts. It's so disturbing if the rules change over time, let's look them up in a book that's at least 2000 years old and not question them. What does the bible say about brushing your teeth?

So, look now, what ever happened to science? Nothing. But presenting only the outcome leaves out the process. And today when every piece of discussion is documented and reaches the public almost immediately, I'd think it's about time that people begin to understand how science works, and that investigation takes time during which there is uncertainty.

Of course scientists disagree with each other. They argue about the interpretation of facts, they argue about data analysis, they argue about the assumptions in their calculations, they argue about which approach is more suitable for which problem, or which conclusion more plausible, who said what first, and which place to go for dinner. You should be worried if they didn't argue, because that's what keeps science alive and healthy. And while scientists investigate the evidence and look for missing pieces their opinions might differ and change.

These processes take time. Questions can be around for decades and they get settled only gradually, until they become established knowledge.

Take for example neutrino oscillations. In first experiments starting with Raymond Davis in 1968 it was found that neutrinos from sun were only measured to be about one third of the prediction, which became known as "The Mystery of the Mission Neutrinos". It was proposed the observations could be explained with neutrinos decaying, or oscillating, or maybe there's something we don't understand about the sun, or maybe the measurement is just wrong. People discussed back and forth. Even I recall that the situation was far from clear and there was a lot of argumentation. More experiments were done. It was shown the effect can occur also for neutrinos from reactor sources and not from the sun. It was observed for neutrinos of different energies. It was shown that not only neutrinos of one flavor go missing, but instead they change into different flavors. The measurements were reproduced numerous times in dozens of experiments. The theory about neutrino oscillation became gradually more established. Today it's textbook stuff. (For a very nice introduction, see John Bahcall's Nobel Lecture - is it a coincidence he chose detectives as illustration?)

Another more recent discussion is the GZK-cutoff, a sudden drop in the spectrum of ultra-high energetic cosmic rays when the energy of the incoming proton exceeds a certain threshold energy. Predicted in the late sixties, it has been claimed to be there, to not be there, then to definitely be there, but there's still people who discuss it as I saw in a paper that was on the arXiv yesterday.

Is there a CMB background or is it pigeonshit?

Or take the Pioneer anomaly. Is it a real effect? Or a systematic problem in the data analysis? Is the situation settled?

Following these discussions and being part of the search is without doubt one of the most exciting aspects of being a scientist. It's quite addictive to hear what's going on, what came out of this experiment, who has a new argument, how does it fit in and what does this mean. And in the age of infotainment when busy bloggers pass on gossip from the corridors to the whole wide world, this search can pretty much be followed by everybody who is interested.

There's two way one can deal with topics that are currently under investigation. One option is to just not talk to the public about anything before there is an established scientific consensus. Problem is, this would make many science journalists unemployed, cause bloggers and their readers withdrawal symptoms, and besides this a public interest in recent scientific research is beneficial for both sides. There would also be the problem to decide when the dust has settled enough, and whether or how that could be decided. This sounds very unappealing to me.

Then the remaining option is learning to live with arguments and uncertainties that come with transparency. That means dropping the idea that scientists are judges instead of crime scene investigators, or have to decide for either side when they instead are collecting the evidence.

“We are faced with all kinds of questions to which we would like unequivocal answers […] There is a huge pressure on scientists to provide concrete answers […] But the temptation to frame these debates in terms of certainty is fraught with danger. Certainty is an unforgiving taskmaker. […] If we are honest and say the scientists conclusions aren’t certain, we may find this being used as justification for doing nothing, or even to allow wiggle room for the supernatural to creep back in again. If we pretend we’re certain when we are not, we risk being unmasked as liars.”

~David Malone, New Scientist, Aug 2007

Anomalous alignments in the CMB - who ordered that? Hole the size of the univserse missing! The Cosmological Constant: Wanted - Dead or Alive.