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Posted by: procyon
« on: February 23, 2012, 02:00:18 AM »

Quote
Further complicating matters, even the OPERA scientists couldn't yet explain why the neutrinos clocked in as fast as they did. Now, according to Science Insider, sources familiar with the OPERA experiment say a fiber optic cable connecting a GPS receiver and an electronic card in one of the lab computers was discovered to be loose. (The GPS was used to synchronize the start and arrival times of the neutrinos).

Tightening the connection changed the time it took for data to travel the length of the fiber by 60 nanoseconds. Because this data processing time was subtracted from the overall time-of-flight in the neutrino experiment, the correction may explain the seemingly early arrival of the neutrinos. To confirm this hypothesis, the OPERA team will have to repeat their experiment with the fiber optic cable secured.

When OPERA announced their results in September, the physicist and TV presenter Jim Al-Khalili of the University of Surrey voiced the incredulity of many in his field when he said that if the results "prove to be correct and neutrinos have broken the speed of light, I will eat my boxer shorts on live TV." It looks as if he, for one, has been spared that level of embarrassment.
Posted by: procyon
« on: September 29, 2011, 02:45:34 AM »

Quote from: Andrew on September 28, 2011, 05:30:07 PM
Its an interesting systematic error if it is one as they have spent a lot of time and effort looking for it. The real test will be if someone else can reproduce the effect , I suspect the answer to this one will not be quick or they would already have solved it. Probably a mistake somewhere though I agree

My bet would be on an error somewhere (whether calibration of time between sites, distance calculations at that moment, etc.).

Although it would be neat to see if someone would run the numbers on the gravatic lensing at this distance.  It could be cool to discover that 'massless' particles are not subject to the gravatic lensing that would distort the measurements of c that could be made here in the Earth's and Sol's gravity well.

What they measured might actually be the 'accurate' c that is nearly impossible to measure using light and an instrument with any mass...
Posted by: Andrew
« on: September 28, 2011, 05:30:07 PM »

Its an interesting systematic error if it is one as they have spent a lot of time and effort looking for it. The real test will be if someone else can reproduce the effect , I suspect the answer to this one will not be quick or they would already have solved it. Probably a mistake somewhere though I agree
Posted by: sloanjh
« on: September 27, 2011, 11:28:26 PM »

Quote from: PTTG on September 23, 2011, 11:32:00 AM
National Geographic

Well, there goes my idea for a hard-science 4x where the speed of light limited communication speed (diplomacy, orders, even unit reports like sensor readings...)

That said, the detectors and emitters would be huge, so it could be that only significant colonies would have the equipment to be connected to the rest of the universe instantly.

It's almost certainly a mistake in the experiment.  Note that the effect that they're getting is ~30 parts per million - it's very easy to miss a systematic error of that size....

And if it is true, be vewy vewy nervous.  Quantum field theory interprets the existence of tachyons (particles that move faster than light) as indication that the vacuum is unstable and may undergo a phase transition (destroying everything) at any moment.

John
Posted by: PTTG
« on: September 23, 2011, 11:32:00 AM »

National Geographic

Well, there goes my idea for a hard-science 4x where the speed of light limited communication speed (diplomacy, orders, even unit reports like sensor readings...)

That said, the detectors and emitters would be huge, so it could be that only significant colonies would have the equipment to be connected to the rest of the universe instantly.