A subatomic particle is challenging the very core of modern physics, after scientists recorded it travelling faster than the speed of light.
According to Albert Einstein's special theory of relativity, which spawned the E=MC2 equation, light is the last word in speed, but neutrinos have now been recorded travelling even faster.
In the Opera experiment, carried out more than 15,000 times over three years, the muon neutrinos – fired in a beam 454 miles between the Cern facility in Geneva to Gran Sasso in Italy – arrived a few billionths of a second quicker than light. The gap was tiny, but its significance is potentially so huge that physicists are struggling to come to terms with its implications.
First, though, researchers want to be sure that they haven't made any errors in their calculations and, having scrutinised the findings themselves, have asked their colleagues around the world to check them. "The feeling that most people have is this can't be right; this can't be real," James Gillies, a spokesman for Cern – the European Organisation for Nuclear Research – told the Associated Press.
"They are inviting the broader physics community to look at what they've done and really scrutinise it in great detail and ideally for someone elsewhere in the world to repeat the measurements."
At Fermilab, a similar facility to Cern – in Chicago – head theoretician Stephen Parke said of the European finding: "It's a shock. It's going to cause us problems, no doubt about that – if it's true." Intriguingly, Fermilab scientists had similar faster-than-light results in 2007, but with such a large margin of error that its significance was undermined.
John Ellis, a theoretical physicist at Cern, who was not involved in the neutrino experiments, said Einstein's special relativity theory underpins "pretty much everything in modern physics" and it has since it was put forward in 1905 "worked perfectly up until now". He added: "This would be such a sensational discovery if it were true that one has to treat it extremely carefully."Reuse content