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and that's how science gets done
March 16, 2012 9:23 AM   Subscribe

Today the Icarus Experiment released their measurement on the speed of neutrinos from CERN. Within small errors, they find them to be traveling at the speed of light, in accordance with the theory of relativity.

This result disagrees with the claim from the OPERA experiment (discussed on metafilter several times), though recently, experimental problems with that result have come to light.
posted by physicsmatt (45 comments total) 7 users marked this as a favorite

 
BIG RELATIVITY GOT TO THEM!!
posted by spicynuts at 9:24 AM on March 16, 2012 [23 favorites]


Surprise!
posted by Arandia at 9:26 AM on March 16, 2012


Phew!
posted by malocchio at 9:28 AM on March 16, 2012


(trains electron microscope on the neutrinos)
(uncovers the fact that the neutrinos are actually wearing heavy lead weights placed labelled "REASON" and "SCIENCE")
(is immediately assassinated by Einsteinian extremists for daring to observe the truth)
posted by Sticherbeast at 9:33 AM on March 16, 2012 [1 favorite]


though recently, experimental problems with that result have come to light.

It would be truer to say "possible experimental problems with that result are under investigation." They found two possible sources of error, one of which could account for the FTL result, one of which would make the result ever FerTL. Certainly this Icarus result makes it seem likely that OPERA will turn out to be based on an error, but "how science gets done" is rigorously checking that out, not dismissing anomalous results out of hand because they don't fit with our current theories.
posted by yoink at 9:36 AM on March 16, 2012 [1 favorite]


I should like to note the amount of scrutiny and time necessary in disproving this claim. In physics we often are able to use a century's formidable calculus to know when a result is probably wrong. Do we have similar machinery in other fields? Can and do we examine other scientific results with the same level of attention and rigor as was required here? In a large number of cases.. I think not.
posted by Algebra at 9:37 AM on March 16, 2012 [2 favorites]


Obligatory Homer 'WE OBEY THE LAWS OF PHYSICS IN THIS HOUSE!' quote.
posted by GallonOfAlan at 9:43 AM on March 16, 2012 [3 favorites]


All Science is either physics or stamp collecting

posted by CautionToTheWind at 9:43 AM on March 16, 2012 [2 favorites]


Peer review... when it works, it works eh chaps?
(and it does work, I assure you)

This is *S C I E N C E* in action, and it's why OPERA published what they did.
posted by Homemade Interossiter at 9:43 AM on March 16, 2012 [1 favorite]


My alternate theory, which is that neutrinos actually always travel at exactly 88 MPH, and only appear to move faster due to time travel, was rejected by the physics community without, I thought, proper consideration.
posted by jcreigh at 9:44 AM on March 16, 2012 [1 favorite]


So, no warp drive, then?
posted by Curious Artificer at 9:45 AM on March 16, 2012


We are already in warp drive.
posted by swift at 9:46 AM on March 16, 2012


Neutrinos are jerks, man.
posted by tommasz at 9:47 AM on March 16, 2012 [1 favorite]


Peer review... when it works, it works eh chaps?

True, but this isn't quite what is usually meant by "peer review." "Peer review" is what is done on results submitted for publication. For example, peer review of the OPERA results might possibly have uncovered the potential sources of error in their experimental design. This is "independent confirmation" (or, in this case, disconfirmation).
posted by yoink at 9:48 AM on March 16, 2012 [1 favorite]


I like stamps.
posted by The 10th Regiment of Foot at 9:48 AM on March 16, 2012 [1 favorite]


the pub faster than anyone else after all. Good to know that neutrinos can't get into
posted by PapaLobo at 9:49 AM on March 16, 2012 [6 favorites]


I was going to post this, but my computer is powered by those slow-assed neutrinos.
posted by dances_with_sneetches at 9:53 AM on March 16, 2012 [1 favorite]


BIG RELATIVITY GOT TO THEM!!

Nonsense, relativity is just an abstract concept. No, you've got to follow the money: Clearly this was the work of the entrenched electromagnetic communication interests at Big Telecom. Does anyone here really think AT&T, Comcast, and their ilk are above corrupting science in order to keep us dependent on their photons and electrons? Wake up sheeple!
posted by jedicus at 9:57 AM on March 16, 2012 [4 favorites]


So, to recap....

Scientists: We've discovered a faster than light particle: neutrinos. This makes no sense. We think we screwed up. Can the scientific community check our work, please?

Internet: SCIENCE!!!WARP DRIVE IS POSSIBLE! WARP NINE, MR. SULU!

George Takei: Oh, my.

Scientific Community: Looks good. We couldn't find anything. This changes the entire field of physics we know it. Better check again.

Internet: THIS WARP DRIVE GOES TO ELEVEN, BABY!

Second Set of Scientists: We tried a smaller batch and confirmed your initial results.

Internet: LET'S ALL PONDER THE MAJESTY OF THIS MOMENT. AT WARP SPEED!!!!!

CERN: Looks like a GPS clock wasn't quite plugged in correctly. Let's check again.

Internet: ARE YOU FLIPPING KIDDING ME?

Scientists: We have the results from the latest experiment and... oopsie. Our bad. Sorry. All Hail Einstein. You can stop shredding your textbooks, now.

Internet: YEAH, BUT WE CAN STILL TIME TRAVEL IN A GODDAMNED DELOREAN, RIGHT? RIGHT?!
posted by zarq at 9:59 AM on March 16, 2012 [17 favorites]


All they show is they were travelling the speed of light while they where doing the experiment. Doesn't prove anything.
posted by Ad hominem at 10:00 AM on March 16, 2012


Us poor schlubs stuck in the basement with the lockin amps and dewers of LHe were complaining about those damn particle types just the other day...even their mistakes result in huge media circuses.
posted by Chekhovian at 10:05 AM on March 16, 2012 [1 favorite]


Scientists: We've discovered a faster than light particle: neutrinos. This makes no sense. We think we screwed up. Can the scientific community check our work, please?

Internet: SCIENCE!!!WARP DRIVE IS POSSIBLE! WARP NINE, MR. SULU!
The internet is so dumb.

Everyone knows that warp nine would tear the ship to pieces, with the possible exception of extremely short bursts, and then only if you've got Scotty holding the ship together.
posted by Flunkie at 10:05 AM on March 16, 2012


I am let down by this. Though irrelevant to my life, the thought of any big science breakthrough such as breaking the speed of light is always interesting.
posted by amazingstill at 10:06 AM on March 16, 2012


Actually, zarq, the Internet I saw was almost entirely skeptical. Myself, I saw zero people cheerleading for warp drive. The science "reporting" was much worse than anyone I saw opining online.

I'd characterize it as more:

Scientists: Hmm, we got a funny result here. Help?

Science media: OMG FTL TRAVEL WARP DRIVE OH GOD OH GOD

Internet, other scientists: This is extremely unlikely, almost certainly experimental error.

Initial scientists: Well, we ran more batches, and we're getting the same result. Not sure what's up, but it's consistent.

Science media: FTL TRAVEL CONFIRMED

Internet: That is just really, really unlikely. Keep checking.

Other scientists: Hmm, we'd better test this ourselves, with our own equipment.

Initial scientists: Oops, a loose connection may have prevented our cable-delay measurement from working correctly.

Internet, other scientists: Aha, that makes sense. Easy thing to miss, but still kinda dumb.

Science media: OMG LOL THEY FORGOT TO PLUG IN A CABLE WHAHAHAHAH MORANS
posted by Malor at 10:15 AM on March 16, 2012 [5 favorites]


Wow! All I can say is that Einstein guy was one smart dude...
posted by Eekacat at 10:17 AM on March 16, 2012


My alternate theory, which is that neutrinos actually always travel at exactly 88 MPH, and only appear to move faster due to time travel, was rejected by the physics community without, I thought, proper consideration.

I think physicsmatt dealt with that theory the last time we had this thread. It would only work if the universal jigawatt constant was within a fairly narrow band (roughly 1.2), and that's easily excluded through experimental means.
posted by Honorable John at 10:18 AM on March 16, 2012 [1 favorite]


Looks like the angelic horde managed to get that bugfix out in the latest universal patch after all.

We're back on track with the rapture people.
posted by zoo at 10:27 AM on March 16, 2012


Malor: " Science media: OMG FTL TRAVEL WARP DRIVE OH GOD OH GOD"

Perhaps we're reading different media?

I never saw any articles that did that. Not even on sites that reported the news, and are devoted to scifi. (io9 even debunked the idea for its readers.) I saw quite a few, (Forbes, the NYT, etc.,) discussing the ramifications of the discovery on physics itself, though.
posted by zarq at 10:31 AM on March 16, 2012 [1 favorite]


Warp Drives kill everyone in front of them.
posted by Artw at 10:35 AM on March 16, 2012


I never saw any articles that did that

Me neither. I did see hundreds of blog-entries, articles and metafilter comments lamenting these non-existant articles, however.
posted by yoink at 11:07 AM on March 16, 2012 [1 favorite]


It would be truer to say "possible experimental problems with that result are under investigation."

"Extraordinary claims require extraordinary evidence", yoink. Any remotely-possible source of error is still more likely to most of the physics world than "c is negotiable."
posted by IAmBroom at 11:10 AM on March 16, 2012 [1 favorite]


OMG they don't agree therefore they don't know anything therefore they are making it up therefore god. Also, everything is just a theory, for one terrible mistaken notion of theory.
posted by clvrmnky at 11:30 AM on March 16, 2012 [1 favorite]


"Extraordinary claims require extraordinary evidence", yoink. Any remotely-possible source of error is still more likely to most of the physics world than "c is negotiable."

Sure. What does that have to do with my statement?
posted by yoink at 11:36 AM on March 16, 2012


"Extraordinary claims require extraordinary evidence", yoink. Any remotely-possible source of error is still more likely to most of the physics world than "c is negotiable."

Actually, to expand a little: the implication of your question is a good example of how the myth of "everybody immediately said that time travel will be possible" sprang immediately into being. I say "it is premature to imply that the specific experimental flaw responsible for the OPERA results has been found" and you hear "OMG, you can't criticize the OPERA results, they just have to be true!!!"

The data-cable thing isn't the first experimental design flaw that has been touted as "the" cause of the anomalous OPERA results, remember. For a while everyone was jumping aboard the "OMG, they don't understand how GPS works!!!" train. Which, of course, turned out to be completely false.

The data-cable thing may very well turn out to be the flaw--and certainly nobody in the world would be placing bets right now on OPERA's results standing up to further scrutiny. But it remains the case that it is premature to imply that the source of the OPERA results has been identified.
posted by yoink at 11:43 AM on March 16, 2012


yoink : Sure. What does that have to do with my statement?

I'm just saying that finding a margin of error big enough to explain the differences darn near closes the book on "Did we find variance in c?"

It may be premature, but the money is now heavily favoring "lab error."
posted by IAmBroom at 11:46 AM on March 16, 2012 [1 favorite]


zarq: I never saw any articles that did that.

yoink: Me neither. I did see hundreds of blog-entries, articles and metafilter comments lamenting these non-existant articles, however.

OMG, don't you see: The Internet actually corrected itself BEFORE it could even make the mistake it corrected!!! This implies time travel. And time travel implies FTL travel. QED.
posted by Hairy Lobster at 1:02 PM on March 16, 2012 [1 favorite]


Artw: "Warp Drives kill everyone in front of them."

we tried to make the Enterprise, but all we got was this lousy Death Star
posted by idiopath at 1:07 PM on March 16, 2012 [2 favorites]


I'm just saying that finding a margin of error big enough to explain the differences darn near closes the book on "Did we find variance in c?"

The book never really opened. It needed more results supporting it to even start sounding plausible.

grumblegrumblefrequentistsgrumble
posted by edd at 1:16 PM on March 16, 2012 [1 favorite]


So Mike Daisey traveled to CERN and stood outside the accelerator counting neutrinos, is what they are saying?
posted by mwhybark at 1:28 PM on March 16, 2012


In physics we often are able to use a century's formidable calculus to know when a result is probably wrong. Do we have similar machinery in other fields?

I think so. Discovering a FTL particle would be akin to, say, discovering that some common animal doesn't use DNA and hatches from stones, or that you can chemically transform lead into gold.
posted by hattifattener at 1:32 PM on March 16, 2012


EINSTEIN.

MESS WITH THE BEST, DIE LIKE THE REST!
posted by Twang at 1:47 PM on March 16, 2012


Obligatory Homer 'WE OBEY THE LAWS OF PHYSICS IN THIS HOUSE!' quote.

Actually, it's "In this house we obey the laws of thermodynamics!" Nothing to do with relativity.
posted by paladin at 2:37 PM on March 16, 2012


Exactly at the speed of light?

How does this square with neutrino oscillation, which implies that neutrinos have a notion of time, hence cannot move at c but must be slightly slower?

I tried to read the paper, but.... Are the error bars they quote consistent with a 2eV (I think?) rest mass for neutrinos?
posted by phliar at 5:39 PM on March 16, 2012


phliar, as you said neutrino oscillation implies that the three known neutrino flavor states (electron, muon, and tau) have non-zero mass squared differences (though the lightest neutrino state could be zero-mass). You are also correct in that this means the neutrinos must travel with speed below c. Figuring out the mass of the neutrino states (rather than the mass squared differences) is very tricky. The current best direct bound comes from tritium decay, where you look for a kinematic end point, and is on the order of 2 eV (the mass squared differences are 10s of meV). Competitive bounds (and perhaps better limits, depending on how well we trust the input assumptions) come from cosmology, but only by a factor of 2 or so. Searches for neutrino-less double-beta decay will be sensitive to much smaller neutrino masses, if they are of the right type.

Will these masses matter for the OPERA experiment? Let's check the numbers. Since the OPERA experiment gets beams from the CNGS at 400 GeV, then taking the largest mass possible for the neutrinos (smaller masses mean faster neutrinos for a given beam energy), the Lorentz factor is gamma = 400 GeV/1 eV = 4 10^11. This means that the speed of the OPERA neutrinos should differ from c by 1/2*gamma^-2 (beta = sqrt(1-gamma^-2), then Taylor expand around gamma^-1 = 0). That is, they should be moving at about 3 10^-24 c slower than c, resulting in approximately a 0.7 femtosecond delay over 732 km compared to a massless neutrino (that's 0.7 10^-6 nanoseconds). The errors in this experiment are measured in nanoseconds, so there's not a competitive bound placed on the neutrino masses from this (you can invert the calculation; take a 1ns delay, figure out the deviation from c that's required, then from that gamma and then the mass).

Just in general, it's pretty standard in a lot of collider experiments to treat many particles as if they are massless. For example, in the LHC detectors at CERN, it is not a bad approximation to pretend that even particles like the b quark (4 GeV) are massless for most simulation purposes, because every other mass and energy in the problem is just so much larger than that. These neutrinos, being ultra-relativistic, are well-modelled by a massless state for this calculation, though you can be sure someone always thinks to check early on to make sure it's a good approximation.

Of course, the whole point of the OPERA experiment is supposed to be measuring muon to tau neutrino oscillations, so you can't ignore the masses in every aspect of the experiment.
posted by physicsmatt at 7:03 PM on March 16, 2012 [2 favorites]


Nothing can go faster than! Nothing can go faster than! NOTHING CANGOFASTER THAN!

GO! (jumps around in music video)
posted by Lipstick Thespian at 6:07 AM on March 18, 2012 [1 favorite]


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