Speed-of-light experiment to be repeated

Researchers at Cern, the world's largest laboratory in Switzerland, announced last month that tiny neutrinos had been observed travelling marginally faster than light.

But the results met with widespread scepticism within the scientific community, not least because Einstein's theory of special relativity – one of the cornerstones of modern physics – makes such a feat impossible.

The results from the Opera experiment appeared to show that the particles had travelled 732km through the Earth from Cern to the Gran Sasso laboratory in Italy marginally faster than light would have done.

According to Einstein nothing should be able to travel faster than light, and evidence that neutrinos were capable of doing so would have a fundamental impact on our understanding of the universe and of time.

The findings were so unlikely and of such critical importance that the researchers chose not to claim a "discovery", instead inviting scientists across the world to scrutinise their data for errors.

Now the team will rerun their experiment with some alterations which they hope will rule out many of the supposed flaws in their findings.

Some critics have argued that the timing measurements – which represent an average figure for a beam of particles rather than direct measurements – may have been misread.

Dr Sergio Bertolucci, director of research at Cern, said using shorter pulses would resolve this problem.

He told the BBC: "In the last few days we have started to send a different time structure of the beam to Gran Sasso.

"For every neutrino event at Gran Sasso, you can connect it unambiguously with the batch of protons at Cern."

Prof Matt Strassler of Rutgers University, who identified possible flaws in the original experiment, said the new test would help clarify the data.

Read more at The Telegraph