[MikeS]

If the neutrinos were going faster than light then they would be going backwards in time.  This would allow them to arrive before light(?).  The time shift would be distance dependant. It would be interesting if a similar experiment were carried out elsewhere but at a different distance.  Seems to me the effect is most likely due to some unaccounted for error.

[Geezer]

I still say they managed to fubar the distance, for no other reason than it appeals to my sense of the absurd  []

[Soul Surfer]

I don't think that anything anomalous does happen on the normal atomic scales but things could very well be different down in dense material (nucleons etc) down at the scale defined by the strong interaction.  This may be one of the very few ways that we could measure these effects because it involves scales of 10^-15 metre and times around the time it take light to travel that distance  ie 10^-23 second.  Remember many cosmologists consider that at very close to the instant of the big bang the velocity of light is in effect infinite.

One of the other things that I have been considering is that quantum mechanical uncertainty is involved in these interactions and this greatly increases the "random noise" in the experiment.  However I cannot see how this could introduce any bias, only a great deal more variation within which this result would be a statistically typical result.   One of the ways this might be tested is to take say four our five subset groups of the results taken at various times and analyse them independently to see if they all individually show traces of this bias.

[syhprum]

is it possible that the true value of c is determined by the speed at which neutrinos travel and that photons travel slightly slower than c ?
Does this mean that we have to redefine the meter ?

[imatfaal]

I don't think so for either case.  the speed of light pops out of maxwell's equations and is fundamental to SR - so if neutrinos go faster then they do; but it does not affect c.  the metre is merely an arbitrary distance - the fact that it is tied in the speed of light in its definition does not mean that it depends on the speed of light for its measurement.  as a mad example - if the great flying spaghetti monster changed by fiat the speed of light to 300,000,000 m/s exactly - we would not change the length of our metres, we would merely redefine the metre to the distance light travels in 3*10^-8 sec (or maybe something else entirely, less at the whim of a mad god)

[yor_on]

There will be found to be something weird involved here, either a mistake of some kind, or 'tunneling' 'backward time travel' 'distance shrinking' whatever. But I'm willing to bet that it won't change 'c' as the constant it is, also that it won't mean that we ever will be able to 'time travel' backwards..

[butchmurray]

Ocam would also tell us that gravitational forces are speeding the acceleration of the expansion of the universe. But since we know what gravity is and that it could cause something very much like we are experiencing if the sources were in the correct positions and they could be the hiding places of the missing mass it would be too easy. So let’s come up with some negative gravity or dark energy and think of something else whimsical to answer the mass question. That’s the way we roll!

Too cynical?

[MikeS]

Presumably the neutrino beam was made up of both neutrinos and anti-neutrinos?
If so then it is certainly conceivable that the anti-neutrinos were going backwards in time which would make them appear to be going faster than the speed of light.

[imatfaal]

Mike - the paper only mentions neutrinos (but it would as the timing would be identical).  the neutrinos were formed by decay of pions (and kaons)

π⁺ -> μ⁺ + ν_μ

π^- -> μ^- + antiν_μ

Frankly I cannot find which form was happening - and as neutrinos are uncharged they could be their own anti-particle - does it really matter.

[MikeS]

Mike - the paper only mentions neutrinos (but it would as the timing would be identical).  the neutrinos were formed by decay of pions (and kaons)

π⁺ -> μ⁺ + ν_μ

π^- -> μ^- + antiν_μ

Frankly I cannot find which form was happening - and as neutrinos are uncharged they could be their own anti-particle - does it really matter.

If they are their own antiparticle then no it does not matter.  However, if they are not their own antiparticle, if they have mass for example then conceivably they could be going backwards in time in which case it would matter, a lot.

[imatfaal]

They can be shown going backward in time on a feynmann diagram and quantum states of particle and anti-particle are interchangeable under cpt reversal - but they do not undecay and they do not travel backwards in time in a lumpen reality sort of way. 

AS an example - the positron in a PET scan can be perfectly calculated in qed etc by thinking of them as an electron travelling backwards in time - but to make a picture of the inside of your head they are a positron going forward in time