A new experiment appears to provide further evidence that neutrinos can travel faster than light, contradicting Einstein's theory of relativity that underpins modern thinking of how the universe works.
Albert Einstein published his theory of relativity in 1905 and asserted that nothing - no matter how small - can travel faster than the speed of light, which is approximately 186,000 miles per second.
The experiment, which is the second of its kind this year, took place at the Gran Sasso laboratory in Italy and used a neutrino beam from CERN in Switzerland 450 miles away.
Scientists at the Italian Institute for Nuclear Physics (INFN) said in a statement that their new tests aimed to exclude one potential systematic effect that might have affected the original measurement.
"A measurement so delicate and carrying a profound implication on physics requires an extraordinary level of scrutiny," said Fernando Ferroni, president of the INFN.
Scientists were shocked in September when a similar experiment found that neutrinos had travelled faster than light and - in theory - arrived at their destination before they set off.
Reuters reports that physicists involved said they had checked and rechecked anything that could have produced a misreading before announcing what they had found.
In an attempt to rule out any margin for error, the beams sent by CERN in this latest experiment were a few nanoseconds shorter than those sent in the September experiment, with larger gaps of 524 nanoseconds between them, resulting in more accurate timing.
"In this way, compared to the previous measurement, the neutrinos bunches are narrower and more spaced from each other," the scientists said. "This permits to make a more accurate measure of their velocity at the price of a much lower beam intensity."
Although errors can still not be completely ruled out, this evidence does further suggest that Einstein's theory of relativity was incorrect, forcing a major rethinking about how the cosmos works. It may even mean that sending information back in time could be made possible.