Original URL: http://www.theregister.co.uk/2012/02/22/cable_fault_caused_opera_result/

OPERA grabs spanner, fixes kit, and slows down neutrinos

Ye canna break the laws of physics, it seems

By Richard Chirgwin

Posted in Science, 22nd February 2012 20:59 GMT

According to a breaking report from Science, last year’s famous faster-than-light neutrino finding has been attributed to a cable fault.

The report says insiders at the OPERA collaboration have found that “a bad connection between a GPS unit and a computer may be to blame”.

The experiment last year seemed to identify neutrinos completing their trip between CERN at Geneva and Gran Sasso 60 nanoseconds too quickly. This result, apparently at odds with Einstein’t oft-confirmed Special Theory of Relativity (which sets the speed of light in a vacuum as a universal maximum), sparked excitement and skepticism around the world in equal measure.

It also set the physics section of the Arxiv open-access scientific database alight, with dozens of papers re-analysing the results or, alternatively, seeking explanations.

Back in OPERA, it seems, scientists and techs were also paying attention to more mundane matters, including the equipment used to make the measurements.

Here, if today’s report is correct, we find the very mundane explanation for the measurements: the poorly-terminated cable between the computer and GPS receiver introduced a signal delay.

After tightening the connection (in other words, El Reg would speculate, eliminating a tiny gap between the end of the fibre and the sensor to which it terminated), OPERA researchers have found that the GPS data arrived 60 nanoseconds earlier than was measured during the original experiment.

"More data will be needed to confirm this hypothesis", says the report. ®