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Faulty Cable To Blame For Superluminal Neutrino Results
smolloy writes "It would appear that the hotly debated faster-than-light neutrino observation at CERN is the result of a fault in the connection between a GPS unit and a computer. This connection was used to correct for time delays in the neutrino flight, and after fixing the correction the researchers have found that the time discrepancy appears to have vanished."
I am glad they went through the proper process of verifying all the hardware and have gotten to the bottom of this little fiasco - but wow, they have to be biting their lips in frustration.
I also expect a cable manufacturer is likely to be getting a strongly worded email in the near future.
Moved to http://soylentnews.org/. You are invited to join us too!
It should read "Faulty Cable Most Likely To Blame For Superluminal Neutrino Results". They haven't proved anything yet. They just found a problem that's very suggestive and they need to re-run the experiment after fixing/accounting for the problem.
Need a Python, C++, Unix, Linux develop
There's no definite statement from OPERA or CERN yet. Right now this is just a rumor. This also is definitely not the first suggested explanation. Let's wait and see.
By my watch...
Nullius in verba
Did they remember to plug it in with the direction marks pointing to the computer?
When you have nothing left to burn you must set yourself on fire
A neutrino walks into a bar. The bartender says, "We still don't serve neutrinos here".
Is there any way we can pin this on Julian Assange?
Give me Classic Slashdot or give me death!
That's why I use Monster Cables for my neutrino experiments. It increases the roundness of the bass end, creates a punchier mid-range, and makes my neutrinos less superluminal.
We will never get off this rock. Interstellar travel is impossible, and always will be.
We will all grow old and die here, and that's it.
at the moment they have merely found out that "data" sent over the fiber-optic cable arrives 60ns earlier then assumed
How does that happen? I've worked at fiber using telecom companies since 96 (customer and provider sites) and I've never heard of a loose cable causing 60 ns of constant delay. Random jitter as the connector bounces around? OK yeah. Intermittent loss? OK yeah.
You can trivially make a fiber "60 ns longer" but thats quite a length of extra fiber, not a tiny fraction of an inch.
My guess is someone thought they were purchasing a X yard long fiber cable, but the helpful installers put in a X meter long fiber without telling anyone, and the stereotypical telecom BS about loose connectors is the coverup for the situation. Or the gear is buggy, it stopped being buggy, and all the tech did was tighten the connectors, so "it must have been the connector". Uh huh, yeah, heard that one before.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
I love the 'Faster than light neutrino' story. It shows something about how science works... an unconfirmed but sensational result captures our imagination. Though fascinating, it is treated with skepticism by scientists including the group publishing the results. Alternative hypotheses challenging the result are examined, and many discarded.
Eventually the result will be supported by more experiments or found to be incorrect... maybe even the result of a loose cable.
The neutrino story also shows something about how science is reported in much of the press... Unconfirmed but sensational results are presented as true. Preliminary challenges to the result are also reported as true. By the time the story is done, news outlets have misreported a number of contradictory claims as fact. No wonder a significant subset of the population doesn't understand or even believe science.
Even the off-shored level1 tech support guy could have figured it out by reading step 2 of his manual.
Right on the money ... http://xkcd.com/955/
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
at the moment they have merely found out that "data" sent over the fiber-optic cable arrives 60ns earlier then assumed
How does that happen? I've worked at fiber using telecom companies since 96 (customer and provider sites) and I've never heard of a loose cable causing 60 ns of constant delay. Random jitter as the connector bounces around? OK yeah. Intermittent loss? OK yeah.
You can trivially make a fiber "60 ns longer" but thats quite a length of extra fiber, not a tiny fraction of an inch.
My guess is someone thought they were purchasing a X yard long fiber cable, but the helpful installers put in a X meter long fiber without telling anyone, and the stereotypical telecom BS about loose connectors is the coverup for the situation. Or the gear is buggy, it stopped being buggy, and all the tech did was tighten the connectors, so "it must have been the connector". Uh huh, yeah, heard that one before.
A television repairman is condemned to Hell for his practices of deceiving and overcharging customers. On his orientation tour of the netherworld he is led past people boiling in pits of lava, having their organs pecked out by beasts and others being flayed, over and over. Thus his fear is great as he is taken down a cavern to his own assignment of eternal doom. A demon shows him to a door, which he opens to find leads to a seemingly endless cavern piled high with television sets, DVD players, cable decoders, etc. "You must fix each and every one of them", proclaims the demon. The repairman relaxes and says, "Well, that doesn't seem so bad after all." "Ah," replies the demon, "but every one of them has an intermittent problem."
A feeling of having made the same mistake before: Deja Foobar
It's cute how you think there's some responsible way to inform the press of an anomalous experimental result.
The scientists just did the same thing you'd do if you got some weird result on a browser-based application, and the preliminary obvious steps didn't fix the problem: check to see if everyone else is seeing the same thing on their browsers, so to speak.
It's not their fault if someone in Marketing hears what's going on and writes a company-wide email saying "BROWSERS CAPABLE OF MAGIC!!! Film at eleven!!!"
The results could be wrong, but for another reason. When trouble shooting you usually think of dozens of potential way things could have cause the problem before tracking down the actual root cause. Jumping to conclusions simply gets everyone's hopes up that the mystery has been solved.
It was a bad cable.
Period.
So if you were in charge, you would just stop looking for the root cause which may go on to taint other results at CERN for years to come? Nothing is certain until it has been confirmed.
Maybe an impedance mismatch at the end(s) of the cable caused the biggest part of the signal to reflect back and forth a couple of times, over the entire length of the cable?
60ns delay is 18m of cable.
Or 6m of cable in which the signal bounces back and forth once.
ADC GPS
ADC ----- GPS
With all due respect, nothing personal, but the ideas you expressed are completely wrong. Kids need to learn that science is experimenting and debating and arguing and trying things that mostly don't work but sometimes they do. There is no cabal and smart people sometimes disagree, most importantly they disagree in a civilized manner. And getting excited and theorizing and double checking your work and then triple checking your work and lots of sweat and effort and long hours. Initial results are sometimes wrong. Where do errors come from? And sometimes how you deal with "failure" defines who you are, more than how you deal with "success".
Science is not (or should not be) a scholastic endeavor that we should try to make as boring and authoritarian and slow and uninteresting as possible. If anything try to make it the opposite, at least a little bit.
If this whole story makes one kid think, just a little bit, about physics, that makes it OK. This is the best thing thats happened to physics in years.
If science were as flaky as a reality TV show, then I'd support your position because somewhere in between is the greek ideal. But... there's a long way to go before we have to worry about that.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
These scientists were irresponsible in their dealings with their press.
I never saw a single irresposible statement from them. They were very clear that there was likely to be an error in their experiment. The press wasn't irresponsible either. Every article I read was balanced and careful to state that there may be a simple explaination.
They should have kept it strictly within the community ...
Who exactly is "the community"? Scientists are not a priesthood, and the public does not need to be "protected" from scientific debate.
Maybe an impedance mismatch at the end(s) of the cable caused the biggest part of the signal to reflect back and forth a couple of times, over the entire length of the cable?
60ns delay is 18m of cable.
Or 6m of cable in which the signal bounces back and forth once.
ADC <----- GPS
ADC -----> GPS
ADC <----- GPS
Uh many, many people predicted that it would turn out not to be true. An error was considered the most likely explanation from the beginning, even by the publishers.
And much like the XKCD author, everyone who predicted that it wouldn't be true would have been ecstatic to be wrong.
What I find much more amusing is all the people who instantly jumped on the result and assumed it was true and proof of whatever they wanted it to be proof of -- from 'science is all a lie' to 'my replacement for Relativity which The Man has stifled is now proven correct!'
The enemies of Democracy are
Bollocks, I am pretty sure it was always explained as an unexpected result, not a new discovery.
How would they do that?
It is far better for the public to see scientists acting openly, showing their data and asking for help. Science is a process, not a result. Trying to get the public to trust science by hiding things from them is precisely the wrong way to go about it. It is akin to suggesting they should trust the scientist because the scientist is always right rather than because the process of science works.
Boffoonery - downloadable Comedy Benefit for Bletchley Park
The bartender says "We don't allow your kind in here".
A faster-than-light neutrino walks into a bar.
Have gnu, will travel.
Sorry but you are going to have to start shoveling. Consider that GPS can routinely produce location solutions measured in tens of meters in a small fraction of a second. Also consider that if you avarage the time signals recovered over long periods of time you can generate time bases that are very high granularity. I'll Quote from NIST.gov... "Tests between widely separated receivers have demonstrated standard uncertainties for time comparisons of less than 10 ns and relative standard uncertainties for frequency comparisons of less than 1 x 10-13, both for averaging times of 1 d. The frequency uncertainty decreases as the averaging time increases. The frequency uncertainty is limited by the relative standard uncertainty of the NIST primary frequency standard which is 2 x 10-15." That's not even for GPS, but for ground based radio. GPS is similar accuracy and 1x10-13 is better than a pico second after a day of observations.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
However the way to deal with this is to have several different models GPS units connected to several different computers and verify synchronization. That is not easy at the level of precision we are talking about here, though. So I do not blame them. And they wisely never did a sensationalist press=release, just "this is what we see and we do not understand it". Now they do. These things can happen.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
So, it seems that the previously calculated stddev was -5.9/+8.3ns, which is about double the certainty of the best COTS systems (it had better be, they're plugged directly into atomic clocks). Basically:
"A loose connection between the fiber link from a GPS receiver to a computer is thought to cause the 60 nanosecond delay; tightening the connection makes the delay through the fiber decrease. However, additional data has to be taken to test the hypothesis. A second error with the crystal oscillator is expected to have lengthened the reported flight-time of neutrinos. Repeat tests with short pulsed beams have been scheduled for May. The two errors affect the result in opposite ways. The OPERA collaboration has not released quantitative estimates of how the errors affect the results, and expect to check the effects directly when a bunched beam is available later in 2012."
So this thing is far from over...
Einstein was seen chuckling to himself and mumbling under his breath "you didn't think it was going to be that easy, did you?"
Aaaaand the inner workings of Star Trek's Heisenberg Uncertainty Compensator is now discovered... it's just a mass of poorly connected wires and circuits! Next step - teleportation...
Scotty would be ashamed of this comment. Surely any Starfleet engineer worth his rating would know its not just the poorly connected wires. Its know which of the poorly connected wires needs to be connected to the phase transition coil and cross circuited to the the pattern buffer.
Its usually the green one.
There is a faulty assumption underlying the notion of the infeasibility of civilization off this planet. That faulty assumption has a name -- planetary chauvanism ... Planetary Chauvinism
... Space Habitat
...L5 - A Hard Science Fiction Series
No breakthroughs in physics or engineering would be needed to build O'Neill cylinders that could eventually create habitable land areas several times that of the earth.
So we can't claim it's impossible. Maybe we'll never do it because, as a species, we can't seem to stop wasting talent and energy on killing each other over borders and religions -- But not because it's impossible.
By the way, an O'Neill cylinder is used in the new hard science fiction web series "L5". They only tease you with a few glimpses in the opening episode, but if they get enough support, they'll make more.