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New Tests Support Claim That Speed Of Light's Been Broken

A 2010 light installation entitled 'Speed of Light' in London.
Ben Stansall
AFP/Getty Images
A 2010 light installation entitled 'Speed of Light' in London.

It's not the final word, but scientists at the Italian Institute for Nuclear Physics report today that "new tests conducted at the Gran Sasso National Laboratory of INFN by the OPERA Collaboration, with a specially set up neutrino beam from CERN, confirm so far the previous results on the measurement of the neutrino velocity."

Translation: They think they've got evidence to support the earlier claim that they had "measured particles traveling at a speed greater than the speed of light," as Adam Frank has written over at the 13.7 blog.

And as Adam said back in September when the original claim was made:

"If this result were true ... then the structure of the world might be very different from what we believe. Einstein's theory of relativity is built on the idea that there is an absolute cosmic speed limit — that light is the thing traveling at this speed is beside the point. Among other things, the existence of that speed limit sets the structure of causality in the Universe.

"In other words, that effects follow causes and not the other way around, which is, in general, a good thing. The universe would be a whole lot harder to understand without this link between cause and effect. Think of it as being shot before the trigger is pulled."

The BBC says the Italian scientists conducted "an improved version of their experiment" to get the new data. "Critics of the first report in September had said that the long bunches of neutrinos (tiny particles) used could introduce an error into the test. The new work used much shorter bunches."

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Mark Memmott is NPR's supervising senior editor for Standards & Practices. In that role, he's a resource for NPR's journalists – helping them raise the right questions as they do their work and uphold the organization's standards.