Skip to content

Faster than light?

Much hoopla over the results of the recent CERN experiment. It claims to have clocked neutrinos travelling faster than light. Could this be the clue to a revolution in physics?

Yes it could, but it is far more likely to be a mundane error. The neutrinos were travelling along a track about 730km long, so at light speed, they would have taken about 0.0024 sec = 2,400,000 ns (n is the SI prefix for a billionth). They are actually supposed to have taken 60 ns less than that. That is a 0.0025% difference.

If the clocks at the two ends were not quite accurately synchronised, or if they were not quite triggered at the right moment, that could easily account for the difference. Or if the distance was over-estimated by 18m, that could account for the difference.

It is made much worse by the fact that we are not talking about single neutrinos being clocked at each end. We are talking about 10,500ns bursts of neutrinos leaving from a range of (unknown and) different places in a 1,000m long tunnel and arriving over a period of similar length at the other end. Elaborate statistical calculations are then used to deduce their flight times. So the burst length and the tunnel length are both more than 50x the error (60ns or 18m) needed to explain the result. My money would be on a duff calculation.

Anyone wanting instant temporary fame could waste a few hundred hours poring over the details.

Post a Comment

Your email is never published nor shared. Required fields are marked *