Scientists reject rivals' light-speed claims
Last September, scientists involved in the international Opera experiment said that a beam of neutrinos had arrived 60 billionths of a second faster than light would have travelled from the underground particle physics laboratory at Cern in Geneva to the Gran Sasso facility in Italy, 466 miles away. Over the weekend, the Opera scientists said they had repeated the experiment with minor modifications to the length of the particle beam to take into account a possible source of error. They said they found the same result – neutrinos that could travel faster than light. Under Einstein's theory of relativity, nothing can travel faster than the speed of light. Otherwise, it would be possible to travel through time.
Now a second group of scientists, part of the Icarus collaboration, has re-analysed the same beam and concluded that the particles could not have travelled faster than light speed without exhibiting a fall in energy levels, which was not detected.
The re-analysis of the same neutrino beam by the Icarus group of physicists is the first serious study to question the "faster-than-light" findings that have astonished and confounded scientists in equal measure. Physicists involved in the Icarus collaboration have posted the new interpretation of the Opera's results on a scientific website stating that the neutrinos would have lost discernible amounts of energy had they travelled faster than the "universal constant" of light speed – about 186,282 miles per second.
As this was not the case, the particles could not have travelled faster than light, the Icarus team said. "Our results therefore refute a superluminal [faster than light speed] interpretation of the Opera result."
