Friday, October 14, 2011

‘Relativity Busted’ Busted?

From Technology Review:
About those speedy neutrinos:

“Today, Ronald van Elburg at the University of Groningen in the Netherlands makes a convincing argument that he has found the error. ..

The time of neutrino flight is harder to measure. The OPERA team says it can accurately gauge the instant when the neutrinos are created and the instant they are detected using clocks at each end.
But the tricky part is keeping the clocks at either end exactly synchronised. The team does this using GPS satellites, which each broadcast a highly accurate time signal from orbit some 20,000km overhead. That introduces a number of extra complications which the team has to take into account, such as the time of travel of the GPS signals to the ground.
But van Elburg says there is one effect that the OPERA team seems to have overlooked: the relativistic motion of the GPS clocks.

If it stands up, this episode will be laden with irony. Far from breaking Einstein's theory of relatively, the faster-than-light measurement will turn out to be another confirmation of it.
Ref: arxiv.org/abs/1110.2685: Times Of Flight Between A Source And A Detector Observed From A GPS Satellite.