This story has gone back and forth, but CERN thinks they have confirmed their original results - and yes, neutrinos are faster than light.
“One key test was to repeat the measurement with very short beam pulses from CERN,” the agency noted in a press release on its website. “This allowed the extraction time of the protons, that ultimately lead to the neutrino beam, to be measured more precisely…The new measurements do not change the initial conclusion.”
The initial experiment, carried out using CERN’s OPERA instrument in Gran Sasso, Italy, involved firing longer beams of neutrinos from CERN’s facility near Geneva, Switzerland, which each lasted 10 microseconds (10 millionths of a second) some 454 miles away to the facility in Gran Sasso.
The new experiment altered this model by firing 20 new, shorter pulses, each lasting 3 nanoseconds (3 billionths of a second), separated by intervals of 524 nanoseconds, in an effort to overcome the margin of error in the first experiment.
They are still not quite ready to declare General Relativity dead.
Elburg argued persuasively in a scientific paper published online in October that the satellites’ timing was affected by their motion in orbit relative to the neutrino beams and the two particle laboratories down on Earth. From the perspective of the satellites, the neutrinos were moving away from one laboratory and toward the other, but the laboratories were also moving, with the receiving laboratory in Grand Sasso appearing to move toward and into the neutrino stream fired by the laboratory in Geneva, thus accounting for the faster-than-light result.
CERN writes in its press release that “This test confirms the accuracy of OPERA’s timing measurement, ruling out one potential source of systematic error,” however, it leaves the door opent to the fact that GPS relativistic timing could produce an error. As such, CERN may test OPERA again without relying GPS for timing.
And of course science requires independent corroboration of any result.
In addition, the results also need to be re-run independently by other particle physics laboratories, and plans are currently underway for this to occur at the only other two institutions in the world capable of performing the experiment: Japan’s T2K laboratory and America’s Fermilab MINOS experiment in Minnesota. Fermilab previously told TPM that its results were expected in early 2012.
Soon we will know. General Relativity may be about to be tweaked.