Friday, February 24, 2012

Claiming more? Show it! Faster than a speeding neutrino!

Marcello Truzzi, sociologist and founder or co-founder of a number of organizations investigating extraordinary claims, is said to have coined the phrase, "Extraordinary claims require extraordinary proof."  Carl Sagan popularized this phrase as "Extraordinary claims require extraordinary evidence."  And so it is with the recent claim that neutrinos can exceed the speed of light, the proverbial c in e=mc^2.

We posted about this remarkable claim when it first came out (here), and then when the same group claimed to have replicated their own results (here), and of course the story was all over the web.  As it should have been, because if true, it would have overturned one of the most robust theories in physics.  The finding was not only extraordinary, it was revolutionary.  (Ethan Siegel's blog, Starts With a Bang, has a bunch of very fine, accessible and detailed explanations of the whole story as it has unfolded.)

Flaws in the experiment are now being reported.  Here's the piece in Nature, but it's also everywhere -- like on the BBCScience Insider broke the news, and Siegel explains the possible alternative scenarios here.

The same group, OPERA, that made the original finding is now identifying their likely errors.  As the Nature piece explains it:
...according to a statement OPERA began circulating today, two possible problems have now been found with its set-up. As many physicists had speculated might be the case, both are related to the experiment’s pioneering use of Global Positioning System (GPS) signals to synchronize atomic clocks at each end of its neutrino beam. First, the passage of time on the clocks between the arrival of the synchronizing signal has to be interpolated and OPERA now says this may not have been done correctly. Second, there was a possible faulty connection between the GPS signal and the OPERA master clock.
The Science Insider story writes that if the group does the equivalent of rebooting their computer -- simpler, actually; just tightening the connection between the fiber optic cable that connects to their GPS receiver -- that one fix would add those missing 60 nanoseconds back to the neutrino travel time.


Though, the BBC tells the story differently.  As they tell it, OPERA says there's another possible explanation, which has to do with "the oscillator used to produce the events time-stamps in between the GPS synchronizations.  These two issues can modify the neutrino time of flight in opposite directions."   The BBC says that tightening the connection would increase the apparent already ultra-fast speed, while fixing the oscillator would slow it down.  That is, either they are more right, or they know why they're wrong.

So, apparently, within the group there's still hope of a revolution.  They'll keep us posted.  And while they work on tightening up experimental conditions, a group at Fermilab in Illinois and a group in Japan are hoping to test this themselves.

While we leave this to the physicists to sort out, there are still some lessons to be learned for the rest of us. The speed of light is a given in physics -- it has been tested without serious challenge for a century, and any suggestion that it can be exceeded must be met with skepticism. There are simply too many direct experiments, and zillions more indirect ones, that seem consistent with the theory. Were he alive today, Marcello Truzzi would surely have written the neutrino results up in his journal, The Zetetic (The Skeptic).

We don't have the same kinds of laws in Biology, as a rule, but evolution and the nature of genes are aspects that seem to come about as close to fundamental theory as we currently can get. And there are important lessons to learn about life at large, compared with what we learn from the ultra-tiny neutrino.

Whether the speed of light is actually 100.000000000000% constant in every 'vacuum' and every part of the universe, apparently has to do with various theoretical issues or explanatory frameworks that are beyond what we know anything about. However, it is close enough and a robust enough finding that we can argue about whether a neutrino can violate this law at all. Any deviation, no matter how tiny, will grab major headlines and be good for the physics professor business!

We are not qualified to say whether a quadzillionth of a percent deviation from the proverbial c, will change much that is of even theoretical importance. Does every single last photon always stream along at exactly the same speed all the time? That kind of constancy would be basically unprecedented in the word of even science's everyday life. What if it simply showed that c is not an eternally totally fixed value but that photon-travelers, like neutrinos, sometimes hustle, sometimes dawdle a tiny tad?

Be that as it may, we have little if anything that is anywhere near so precise, exact, and universal about life or evolution. The proof of this is how easily--routinely, even--professors and their reporter-acolytes proclaim essentially revolutionary, major, dramatic, or transformative new findings.

A new fossil often is claimed to entirely overturn everything we said we knew about human evolution, or so the media and the discoverer will have you believe (as we have commented recently in MT). A fossil found sucking its thumb would be argued to completely revolutionize our understanding of the evolution of thumbs (and depending on its age at death, perhaps also about the length of childhood in our ancestors!).

In contemporary genetics, which is Gee!Wash in GWAS, first the idea that would revolutionize everything was that common variants cause common disease; then that to a great extent the same gene variants cause the same disease in all populations; then it was rare variants are the culprits to be discovered with wholegenome sequence; then epigenetics; then copy-number variation; then gene regulatory networks. The chain of 'omics' revolutions is, so far, endless. Medicine will be revolutionized by being genomically personalized.

We are truly learning a lot about life, but the major changes in views claimed for each new finding or paper shows clearly that we simply do not have our theoretical 'neutrinos'. Our knowledge is too easy to 'revolutionize' by the next technology that comes down the pike, to be considered theoretically very sound knowledge.

Now, physicists will be melodramatic about whatever is found in those little hyper-travelers, just as biologists are about how every new genetic variant they discover that will guarantee immortality. And, not least of the physicists' worries in all this is whether it will affect their funding. They have their sick side just as we do: that finding out truth will determine whether we can keep our jobs--even though our jobs are, supposedly, to find out truth!

The educated public, and scientists ourselves, need to realize and acknowledge how very far we are from physics-like understanding of life. And given that, and the topsy-turvy claim-laden recent history of genetics, medical genetics, and evolutionary biology, there should be some slowing down, taking stock, and tempering of our claims. When we are this far from absolute truths, and no really sound underlying theory, we have no business over-promising, much less being in such a frenzied (fund-seeking-based) race.

Perhaps it's time for some medicine for our ailment: some sanctions for claiming too much, and not acknowledging the depth of our own loose connections. Or some accountability for real progress in (say) curing disease, rather than the moving target of promises not met. This is because if we had some accountability or didn't rush for headlines and snow-jobs at every turn, we might temper our thoughts as well as our claims, and spend more time and effort understanding how multiple, variable, hard-to-measure causal elements worked together, and varied, in relation to biological traits normal and disease, and their evolution.

We face very challenging and legitimate issues in biology, both to understand evolution and to bring about major biomedical advances. We should be able to make much better progress if we knuckle down more intensely to understand the complexity of life's complexity, rather that slicing and dicing it up into this or that one-size, large-scale, comprehensively enumerative ('omic') style approach that essentially promises to turn complexity into simplicity. We know the professional pressures that push us in the latter direction, and we all feel them, and we inculcate new members of the guild into that environment. But nobody seems to be resisting these pressures.

Basically, like physicists, we should own up to our rather large array of loose connections. Until we do, there is something well-known that's Faster than a Speeding Neutrino. It is the speed with which biologists rush to call a press conference to announce their latest Discovery.

No comments: