Pulsar wrote:

zaybu wrote:It would seem that this issue has been resolved.

No, it's just another proposal, among the countless others. It remains to be seen whether this holds any water.

But now, ScienceInsider is reporting that there was a good reason the measurements and reality weren't lining up: a loose cable was causing one of the atomic clocks used to time the neutrinos' flight to produce spurious results. If the report is confirmed, then it provides a simple explanation for the fascinating-yet-difficult-to-accept results.

Pulsar wrote:You've got to be fucking kidding me. A loose cable?
If this gets confirmed, I can't wait to see the press conference. This is going to be awkward

twistor59 wrote:The physics geek in me wants this explanation to be wrong because SOL variation would stir up physics no end. But the comedian in me wants it to be true....

CdesignProponentsist wrote:I don't think it needs to be awkward. They have always said that there could be a systemic problem with their experiment. Science is a process.

Pulsar wrote:

CdesignProponentsist wrote:I don't think it needs to be awkward. They have always said that there could be a systemic problem with their experiment. Science is a process.

An instrumentation problem was always the most likely culprit, but I did expect a more sophisticated glitch

I suppose it’s possible. But man, that would make the experimenters look really bad. And the sourcing in the article is just about as weak as it could be: “according to sources familiar with the experiment” is as far as it goes. (What is this, politics?)

So it’s my duty to pass it along, but I would tend to reserve judgment until a better-sourced account comes along. Not that there’s much chance that neutrinos are actually moving faster than light; that was always one of the less-likely explanations for the result. But this isn’t how we usually learn about experimental goofs.

But according to a statement OPERA began circulating today, two possible problems have now been found with its set-up. As many physicists had speculated might be the case, both are related to the experiment’s pioneering use of Global Positioning System (GPS) signals to synchronize atomic clocks at each end of its neutrino beam. First, the passage of time on the clocks between the arrival of the synchronizing signal has to be interpolated and OPERA now says this may not have been done correctly. Second, there was a possible faulty connection between the GPS signal and the OPERA master clock.

[...]

“The OPERA Collaboration, by continuing its campaign of verifications on the neutrino velocity measurement, has identified two issues that could significantly affect the reported result. The first one is linked to the oscillator used to produce the events time-stamps in between the GPS synchronizations. The second point is related to the connection of the optical fiber bringing the external GPS signal to the OPERA master clock.

These two issues can modify the neutrino time of flight in opposite directions. While continuing our investigations, in order to unambiguously quantify the effect on the observed result, the Collaboration is looking forward to performing a new measurement of the neutrino velocity as soon as a new bunched beam will be available in 2012. An extensive report on the above mentioned verifications and results will be shortly made available to the scientific committees and agencies.”

iamthereforeithink wrote:Gaaa...aah

And we're trusting these nincompoops to come up with the next big breakthroughs in the field of physics? I'm going to sue these guys on two counts -

1. Monetary loss on account of many hours wasted in the cafeteria discussing possible theoretical explanations. Time which, if spent productively, might have earned me upwards of $100k
2. Defamation, on account of looking like an idiot when I go to the cafeteria tomorrow.

Darkchilde wrote:It's official, just got the CERN Press Release here: http://press.web.cern.ch/press/PressReleases/Releases2011/PR19.11E.html

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.

twistor59 wrote:does the bold part mean "not screwed in correctly" ?

Sean Carroll wrote:.... “according to sources familiar with the experiment” is as far as it goes. (What is this, politics?)