CERN team claims measurement of neutrino speed >c

AlchemistK

http://arstechnica.com/science/news/...oose-cable.ars

So is it a loose cable or a bad connection?

sshai45

If the cable is loose, it doesn't make a good connection.

AlchemistK

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.

sshai45

You sure? This here:

http://www.reuters.com/article/2012/...81L2B820120222

says "a loose fiber optic cable linking a Global Positioning System satellite receiver to a computer."

Passionflower

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.

CaptFirePanda

Yes, because that guy would never make a mistake!

Drakkith

Mistakes happen. There's no reason to suspect all of our results to be faulty based on one mistake in one piece of equipment.

Vanadium 50

Realize that there is no official statement; people are just repeating rumors. Wait a half day.

GTOM

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.

Histspec

There is now an official statement by OPERA:
http://www.nature.com/news/flaws-fou...rement-1.10099
And the press release update from February 23:
http://press.web.cern.ch/press/Press.../PR19.11E.html

They say that there were actually two possible sources of error (in opposite directions), which might significantly influence their former result. They will check it in May.

kmarinas86

Right on.

Enoy

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. "

lmoh

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.

Enoy

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 eachother 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

CaptFirePanda

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.

ardenmann0

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

http://news.yahoo.com/faulty-wire-er...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."

CaptFirePanda

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.