Guest Post: Not So Fast

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The news of a detection of faster-than-light speed neutrinos by the OPERA experiment stunned the physics and astronomy community last week.  I read the paper, and I listened to the talk from Geneva over the Web. This is seriously weird stuff! Faster-than-light speed neutrinos!? The talk was filled with wonderfully arcane geodetic methods for measuring the line-of-sight difference between a proton beam in Geneva and a cave in Italy 730 kilometers away. We experimentalists eat this stuff up. It is so cool to say you can measure the underground distance to an accuracy of 20 centimeters over such a distance, just like it is cool to say that we can measure the changing distance to the Moon to a millimeter or so.

Immediately all scientists began to play with this concept. It is one of the most fun things in science—to be liberated from whatever fussy Standard Model we have, and be allowed to explore a possible new direction for our ideas and experiments.

 As we listened to the talk we had a private conversation in our minds. Is this for real? Can I poke a hole in it? Should I ignore it and risk being left behind on the new physics? Should I try to think up an experiment to test it? Our scientist minds quickly create an intuitive probability spectrum for this discovery in the form:

1. this is just really stupid;
2. they did a good job and and I will let someone else figure out what they did wrong;
3. well, it is probably wrong, but on the slight chance they are right, maybe I can devise a way to explain it before anyone else can;
4. I don’t care if it is right or wrong, I can explain everything;
5. I already knew this was true;

Not surprisingly, the experimentalists cluster toward lower numbers and the theoreticians toward the higher numbers. That is healthy. In the question and answer period, one physicist said he had already submitted a paper to the preprint server explaining this discovery. That guy was definitely a 4 or 5. In respect for full disclosure, I am pretty much a 1 or 2, and those who know me would say I am definitely a 1 or even less.

My intuitive reaction, however, was mostly of sadness.

I was trying to figure out why. Often scientists react to a new discovery because we have been working for five years on a project with little recognition, and along comes something like this and they get all the attention. The green-eyed monster. We secretly wish it is wrong because it just seems unfair they get the rock-star attention and my science doesn’t.

But my reaction was different and I have tried to figure out why. Of course, the result contradicts so much of physics as we know it. We KNOW that neutrinos travel at the speed of light from the almost simultaneous arrival of detected neutrinos and light from the supernova 1987A in the Large Magellanic Cloud. It took 150,000 years for the signal to get to us, and the timing difference was only 3 hours — and there is a simple explanation for even that time difference. Of course, smart theoreticians will say that you can’t compare the OPERA experiment to the SN1987A result. They are different energies, they are different neutrinos, they have more chance to interact with fifth-dimensional strings, yadda-yadda. My eyes glaze over when the first thing you do with a theory is add a new parameter because you can’t fit the observations. But this is the way the game is played—and explains why I am not a theoretician.

But this does not explain my sadness.

Maybe it was the way the experiment was done. There was an obvious flaw in the experiment because it was not set up to measure the time of flight of neutrinos. The histogram for all the flight times looks like a table, and the measurement they made was much like measuring the length of a table. Even if your ruler is good, you’ll have an error.  The error won’t be in the measurement of the table between the edges; that measurement will be accurate. The error creeps in when you measure the very edges. Is the edge sharp—or beveled? What does “edge” mean? The same with this experiment. Almost all the data—the tabletop—between the very beginning of the pulse or the end of the pulse have little weight in the measurement. Only the neutrinos detected at the beginning or end of the pulse will give you the accuracy of the measurement—or inaccuracy. And the experiment wasn’t designed to measure the “edges of the table” with the precision you would need in a time-of-flight experiment.

No, it is not that. I think I can explain my reaction—we are seeing the way that science is done, and where we are going is not clear to me. And perhaps I will be left behind in this brave new world. In my old world, ideas and experiments were judged in the refined environment of workshops, refereed journals, and careful press releases. We now see ideas swept up into an Internet frenzy as we all play with the new idea. Ultimately, I guess this is all healthy. The best ideas will win out.

Or will they? Certainly in this new world, climate change science has become so toxic that a NOAA program studying climate change was axed by the House basically because it had the word “climate” in it. Science by the marketplace; science by politics. The public, not trained in science, will look at the OPERA result, which says that the speed of light is not absolute, as proof that any idea in science is equal to any other.  To a scientist, any idea is equal to another, until you start to think about it, play with it, see if it fits into what we know. Science is cruel to ideas and they get cut to pieces quickly.

So what will happen here? I am willing to bet your retirement account that this result will be shown to be wrong—a careful result that had some flaw. But will that be reported with the same energy as the discovery? Of course not. Thus most Internet users with nanosecond attention spans will not see the process of science as it closes in on this experiment and probably rips it to shreds. And for a scientist this is fun. But there will be little public interest in watching science do what it does best. The public wants to hear of the crazy theories, not the boring work to show that the status quo is probably right.

Today in my department the only topic will be faster-than-light neutrinos. We will play with the idea and probably figure out it does not make sense. It is going to be fun! Hundreds of thousands of scientist-hours around the world will be spent in the next week over this experiment. But the public does not see, nor does it know, about this aspect of science. And it makes me sad that the really fun part, playing with the idea, will never be known to most people. They will only remember the original result, which for the scientists is where the fun begins.

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Nicholas Suntzeff is a professor of observational astronomy and a member of the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, where he heads the Astronomy Group inside the Department of Physics and Astronomy. He specializes in cosmology, supernova studies, and astronomical instrumentation. In fifth grade he received an Honorable Mention for turning his science project in on time.

Traffic cop: © awizemann via flickr; “On the Electrodynamics of Moving Bodies”: The Collected Papers of Albert Einstein: The Swiss Years, Writings, 1900-1909, by Albert Einstein (Anna Beck, translator; Peter Havas, consultant), © 1989 by the Hebrew University of Jerusalem; The Time Tunnel: mptvimages.com.

7 thoughts on “Guest Post: Not So Fast

  1. Sad? I’m a middle-aged, female English major who dropped physics before I could fail it. My kid is a teenager with a learning disability who I was once told might never learn to read. We were both excited about neutrinos this morning. Pre-internet, we wouldn’t have known about it, or if we had it would have been in an article in a newspaper that meant almost nothing. Post-internet, we talked about it over breakfast, and then again in the evening. No, we’ll never participate in the hundreds of hours of scientist excitement (at least I won’t, and he probably won’t either) but I’m not sure why that makes you sad, because it makes me happy to know that we care about something so abstract and removed from our daily lives. For me, the simple fact that we were both excited about science is a little internet miracle worthy of some joy.

  2. If neutrinos from your supernova 1987A had traveled at the same speed that the OPERA neutrinos seemed to be traveling at, they would have reached your detectors before the light did, right? How long before? And would you have seen them?

  3. @ann, it is a testament to the amatuer astronomers around the world that the Large Magellanic Cloud is observed so often that we could pinpoint the time of the optical explosion to within 3 hours. An astronomer in New Zealand saw the SN as it rose to light.

    as for the neutrinos, if you take the 60 nanosecond delay time as the increment in speed for neutrinos from the 730km baseline for the OPERA measurement the neutrino signal should have arrived around 4 years *before* the optical signal.

    the three hour delay time was initially puzzling. It was shorter than expected from a massive star that blew up. But after finding older data which showed which star blew up, it turned out to be a blue supergiant which has a much smaller radius than a red supergiant which is usually what blows up.

    The neutrinos showed that a neutron star formed in the ashes of SN1987A, but so far, no such object has been detected directly.

  4. I worked at JPL doing the Mobile VLBI Project, placing truck-mounted radio dishes at sites around the west and aiming to get the first measure of crustal motion. The project had already been renamed and remanaged after announcing many cm of motion without accounting for the 50 cm of ionosphere delay, it was abandoned when GPS proved more efficient for the short baselines, but I have to echo Barbie:
    “Precision metrology above the ground is hard.”
    I can’t produce an equivalent for underground metrology.

  5. Is the solution not to work harder to change science communication to reflect the real process of science. There is real danger in misunderstandings about climate change, and evolution for that matter, but the only cure is to increase the ability of our audience to critically parse the scientific information before them. Wouldn’t it be great if we could allow everyone to play with ideas, just as your colleagues do?

  6. Greetings to all. Well, to ordinary minds like mine, this news seemed like a breakthrough before you pointed out otherwise. I am no scientist so forgive me if I fall under category 2. 🙂 We grew up being taught (more like brainwashed) at school to just accept facts that have already been proven by renowned scientists (personally, I looked up to you guys as super humans for the geniuses that you are). As much as we would like to join in the fun, it is but unfortunate that we (the non-scientists) don’t have that kind of brain power that you guys have been so abundantly blessed. So, the future of this breakthrough lies in the hands of you guys to see to it that your fellow scientists’ “facts” are indeed facts. It is truly amazing what you guys can do. And thank you for too for explaining the weakness of the experiment in layman’s term. This kind of talk excites my curious mind even if I have nothing to do with it. (And that is why I watch The Big Bang Theory). lol

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