At the speed of light, the neutrinos fly the distance of 732km through rock in 2.44ms. A few billionths of a second would be roughly a million times smaller than 2.44ms. If they didn't make an error, the neutrinos traveled at about 1.000001 times the speed of light. Obviously, they have a high confidence in the precision of all their measurements. For example, they need to know the distance from the source to the detector with an error of less than a meter in 732km. 1.000001c isn't much faster than light, but nevertheless, a lot of physics has to be rethought if they're right.
Here's a link to the published paper. Measurement of the neutrino velocity with the OPERA detector in the CNGS beam http://static.arxiv.org/pdf/1109.4897.pdf Abstract The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured the velocity of neutrinos from the CERN CNGS beam over a baseline of about 730 km with much higher accuracy than previous studies conducted with accelerator neutrinos. The measurement is based on highstatistics data taken by OPERA in the years 2009, 2010 and 2011. Dedicated upgrades of the CNGS timing system and of the OPERA detector, as well as a high precision geodesy campaign for the measurement of the neutrino baseline, allowed reaching comparable systematic and statistical accuracies. An early arrival time of CNGS muon neutrinos with respect to the one computed assuming the speed of light in vacuum of (60.7 ± 6.9 (stat.) ± 7.4 (sys.)) ns was measured. This anomaly corresponds to a relative difference of the muon neutrino velocity with respect to the speed of light (v-c)/c = (2.48 ± 0.28 (stat.) ± 0.30 (sys.)) ×10-5.
Wasn't that long ago when I was being derided for suggesting that the speed of light cannot be an absolute. These findings will probably be proven incorrect, but they do give pause and reinforce the point that none of this is certain. My big beef with relativity is that it's logically self-conflicted. It holds as a precept that space and time are relative rather than absolute, yet they try to establish a concept of "velocity" based on them. Without constant space, there is no constant distance, and without constant time, there is no such thing as constant "velocity", which is necessarily the product of the two. They say that practically all the matter that was created during the Big Bang is missing. They call this "dark matter". I personally don't think it's missing. I think it's just undetectable because it's whizzing around faster than c.
possum got his lil' Star Wars w/ light saber outfit on... Speed-of-light results under scrutiny at Cern 23 September 2011 : Enormous underground detectors are needed to catch neutrinos, that are so elusive as to be dubbed "ghost particles"
Even if this isn't an error it won't be the turning of physics on its head like many people seem to think. Einstein didn't get Newton thrown out of the physics books because Newton works in most cases, as Einstein probably still would. This would probably just be a slight change. Remember, when a new theory comes along it has to include why the old one looked right and is probably still right in most cases.
This is a complicated precision experiment. Since the neutrinos were measured to be traveling at 1.0000248c ± 0.0000006c, my guess is that they did get a detail wrong somewhere. The speed they measured is still a bit too close to the speed of light to get me really excited. If nobody finds a flaw, however, this gets really interesting and their result has to be replicated. Edit: By the way, Panzerkampfwagen is right. We've accelerated billions of particles for many years now and never managed to get one of them past the speed of light despite giving them huge amounts of kinetic energy. The relation E^2 = p^2*c^2 + m^2*c^4 has turned out to be very useful so far and something similar has to appear in a limit of any new theory.
I had the same thought. If that was the case, it would be another affirmation of Einstein. However, I agree with Herby. probably some error in the experiment.
The neutrinos at CERN are at a level of energy much higher than previous experiments. And, actually, MINOS did find similar results in 2007. The different is that in MINOS there was a larger error bar and the fluctuating results could be discounted as statistically insignificant.
