CERN team claims measurement of neutrino speed >c

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CERN's team reported that neutrinos were measured traveling 60 nanoseconds faster than light over a distance of 730 km, raising questions about the implications for special relativity (SR) and quantum electrodynamics (QED). The accuracy of the distance measurement and the potential for experimental error were significant concerns among participants, with suggestions that the reported speed could be a fluke due to measurement difficulties. Discussions included the theoretical implications if photons were found to have mass, which would challenge established physics but might not necessarily invalidate SR or general relativity (GR). Many expressed skepticism about the validity of the findings, emphasizing the need for independent confirmation before drawing conclusions. The ongoing debate highlights the cautious approach required in interpreting groundbreaking experimental results in physics.
  • #691
The announcement, as with many claims of fairly substantial implications, is made as a placeholder of sorts so that, if they are right, no one else has the chance to scoop the claim.

It may be a little hasty, but the announcement is made with a boat load of caveats to set expectations properly.
 
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  • #692
Drakkith said:
Mistakes in general are inevitable. But there's no way to tell where they will crop up.
Luckily CERN was adamante in saying they needed confirmation.

I didn't mean to sound as harsh as that and I agree with you also.
 
  • #694
Histspec said:
It seems that a simple explanation of this result has been found – no superluminal neutrinos, but only a bad connection between GPS and a Computer.

Dang it! I didn't get a chance to get some bets in. I'd have given long odds the report was due to a glitch in the apparatus.

I am surprised the original claim got reported in the first place.
 
  • #695
Drakkith said:
Wooo! Looks like they found the problem! No more Einstein is wrong posts!

Somehow I doubt that "Einstein is wrong" will ever go away. To many out there with nothing other then their gut to guide them and the natural gut reaction is that it cannot be right.
 
  • #697
Integral said:
Somehow I doubt that "Einstein is wrong" will ever go away. To many out there with nothing other then their gut to guide them and the natural gut reaction is that it cannot be right.

But the difference is that in this case they looked like they really had something that might have posed a challenge, not just a "gut feeling". It turned out not to, but still...
 
  • #700
In the earlier news it was about a bad connection between the GPS and the computers, now its about a loose fiber optic cable connecting with atomic clocks.
 
  • #701
AlchemistK said:
In the earlier news it was about a bad connection between the GPS and the computers, now its about a loose fiber optic cable connecting with atomic clocks.

You sure? This here:

http://www.reuters.com/article/2012/02/22/us-physics-neutrinos-cable-idUSTRE81L2B820120222

says "a loose fiber optic cable linking a Global Positioning System satellite receiver to a computer."
 
  • #702
If this loose cable thing is confirmed I think it is very worrying, not for the particular experiment where the Neutrino speed was anomalous but for all other experiments.

All other experiments before and after would have potentially given false data and nothing would have been suspected, only now when we found 'impossible' results do we check.

Seems they need to hire a guy who checks the cables before every experiment.
 
  • #703
Yes, because that guy would never make a mistake!
 
  • #704
Passionflower said:
If this loose cable thing is confirmed I think it is very worrying, not for the particular experiment where the Neutrino speed was anomalous but for all other experiments.

All other experiments before and after would have potentially given false data and nothing would have been suspected, only now when we found 'impossible' results do we check.

Seems they need to hire a guy who checks the cables before every experiment.

Mistakes happen. There's no reason to suspect all of our results to be faulty based on one mistake in one piece of equipment.
 
  • #705
Realize that there is no official statement; people are just repeating rumors. Wait a half day.
 
  • #706
About the Einstein was wrong posts : I think many people want to believe this, because they share the fear, that it makes interstellar travel impossible, and we will be doomed here, and i guess some of them will keep searching.

Well, it would have been really good to see another major breakthrough :(, i wait until they recheck the results.
 
  • #707
Vanadium 50 said:
Realize that there is no official statement; people are just repeating rumors. Wait a half day.

There is now an official statement by OPERA:
http://www.nature.com/news/flaws-found-in-faster-than-light-neutrino-measurement-1.10099
And the press release update from February 23:
http://press.web.cern.ch/press/PressReleases/Releases2011/PR19.11E.html[/URL]

They say that there were actually [B]two[/B] possible sources of error (in opposite directions), which might significantly influence their former result. They will check it in May.
 
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  • #708
Passionflower said:
All other experiments before and after would have potentially given false data and nothing would have been suspected, only now when we found 'impossible' results do we check.

Seems they need to hire a guy who checks the cables before every experiment.

Right on.
 
  • #709
Here is the press release from Cern:

"OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran SassoUPDATE 23 February 2012

The OPERA collaboration has informed its funding agencies and host laboratories that it has identified two possible effects that could have an influence on its neutrino timing measurement. These both require further tests with a short pulsed beam. If confirmed, one would increase the size of the measured effect, the other would diminish it. The first possible effect concerns an oscillator used to provide the time stamps for GPS synchronizations. It could have led to an overestimate of the neutrino's time of flight. The second concerns the optical fibre connector that brings the external GPS signal to the OPERA master clock, which may not have been functioning correctly when the measurements were taken. If this is the case, it could have led to an underestimate of the time of flight of the neutrinos. The potential extent of these two effects is being studied by the OPERA collaboration. New measurements with short pulsed beams are scheduled for May. "
 
  • #710
Enoy said:
Here is the press release from Cern:

"OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran SassoUPDATE 23 February 2012

The OPERA collaboration has informed its funding agencies and host laboratories that it has identified two possible effects that could have an influence on its neutrino timing measurement. These both require further tests with a short pulsed beam. If confirmed, one would increase the size of the measured effect, the other would diminish it. The first possible effect concerns an oscillator used to provide the time stamps for GPS synchronizations. It could have led to an overestimate of the neutrino's time of flight. The second concerns the optical fibre connector that brings the external GPS signal to the OPERA master clock, which may not have been functioning correctly when the measurements were taken. If this is the case, it could have led to an underestimate of the time of flight of the neutrinos. The potential extent of these two effects is being studied by the OPERA collaboration. New measurements with short pulsed beams are scheduled for May. "

Do both effects account for the 60 ns effect together, or is it just the fiber cable? I keep hearing more about the second cause, but very little about the first.

Well anyways this is sort of embarassing. Who've thought that for years, there has been a loose cable in the system and nobody knew about it.
 
  • #711
I will not be surprised if theese two issues only is shown to be of minor significance for the time measurement, when they start up the experiment in the spring coming. The issues even might cancel each other out with regards to time-measurments-errors. The reason for this, I think, is due to the fact that Fermilab also got results for a couple of years ago that showed faster than light neutrinos, but with too big uncertanties to make the result noteworthy. And, also due to the fact that the scientific community lacks both experimental and theoretical understanding of the physical reality inside the reference frame of mass-densities like planets, and how such frames might affects the the physical relations, compared to that we are used to namely empty space/vacuum.

Sincerly
me :smile:
 
  • #712
As mentioned above, CERN has commented on that and another hardware issue that would have resulted in a delayed response to the neutrino's arrival. So there are 2 conflicting hardware glitches at play here.
 
  • #713
Enoy said:
I will not be surprised if these two issues only is shown to be of minor significance for the time measurement, when they start up the experiment in the spring coming. The issues even might cancel each other out with regards to time-measurments-errors. The reason for this, I think, is due to the fact that Fermilab also got results for a couple of years ago that showed faster than light neutrinos, but with too big uncertanties to make the result noteworthy. And, also due to the fact that the scientific community lacks both experimental and theoretical understanding of the physical reality inside the reference frame of mass-densities like planets, and how such frames might affects the the physical relations, compared to that we are used to namely empty space/vacuum.

Sincerly
me :smile:
So you think it's just minor significance. Then how do you explain this:

http://news.yahoo.com/faulty-wire-error-blamed-faster-light-particles-233455932.html

"After tightening the connection and then measuring the time it takes data to travel the length of the fibre, researchers found that the data arrive 60 nanoseconds earlier than assumed," it added.

"Since this time is subtracted from the overall time of flight, it appears to explain the early arrival of the neutrinos. New data, however, will be needed to confirm this hypothesis."
 
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  • #714
ardenmann0 said:
So you think it's just minor significance. Then how do you explain this:

"After tightening the connection and then measuring the time it takes data to travel the length of the fibre, researchers found that the data arrive 60 nanoseconds earlier than assumed," it added.

"Since this time is subtracted from the overall time of flight, it appears to explain the early arrival of the neutrinos. New data, however, will be needed to confirm this hypothesis."

Please read the press release below (it has been posted already). There are thought to be two possible sources for measurement error: one that could have increased the size of the measured effect and one that could have diminished it.

Enoy is considering the possibility the the 2 effects might cancel each other out and the 60 μs anamoly would remain as such.


Enoy said:
Here is the press release from Cern:

"OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran SassoUPDATE 23 February 2012

The OPERA collaboration has informed its funding agencies and host laboratories that it has identified two possible effects that could have an influence on its neutrino timing measurement. These both require further tests with a short pulsed beam. If confirmed, one would increase the size of the measured effect, the other would diminish it. The first possible effect concerns an oscillator used to provide the time stamps for GPS synchronizations. It could have led to an overestimate of the neutrino's time of flight. The second concerns the optical fibre connector that brings the external GPS signal to the OPERA master clock, which may not have been functioning correctly when the measurements were taken. If this is the case, it could have led to an underestimate of the time of flight of the neutrinos. The potential extent of these two effects is being studied by the OPERA collaboration. New measurements with short pulsed beams are scheduled for May. "
 
  • #715
There is an interview with Dario Autiero (spokesman of OPERA), providing some details on both errors.

http://www.nytimes.com/2012/02/24/s...-because-of-technical-problems-cern-says.html

Regarding the first source of error that might increase the neutrino velocity, no numbers were given. However, then it is said regarding the second source:

The investigation discovered that for dimmer light pulses, the circuit receiving the data introduced delay — up to 60 billionths of a second — that could bring the neutrinos’ speed back under the speed of light.

There we have the 60ns again.

Regards,
 
  • #716
"Second, there was a possible faulty connection between the GPS signal and the OPERA master clock."

Havent they tryed, whether normal radio signals arrive 60ns earlier than expected?
(In some smaller surface experiment, to test the timing?)
 
  • #717
Have the theoreticians been informed?
It would be ruthless to let them waste their time any longer.
 
  • #718
It's good they found errors themself. Otherwise it would be a shame, especially when MINOS will spend couple millions to find their errors.
 
  • #719
lalbatros said:
Have the theoreticians been informed?
It would be ruthless to let them waste their time any longer.

Serious theoreticians do not respond to the "discovery" of overturning all of modern physics.
 
  • #720
"Serious theoreticians do not respond to the "discovery" of overturning all of modern physics."

Sorry, i don't want to be rude, but IMHO, they shouldn't have cared about theory of relativity in the first place, if they had shared this mentality. Maybe the experiments were all faulty, they didnt check their apparatus...

Okay, of course everyone can commit errors, it can be pretty hard to find them, especially in such a case, i just don't understand, if there was such an error, and not a couple of tiny errors that accumulated, how could they not determine, that in general, timing is delayed with that much?
 

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