After Follow-Up Tests, Neutrinos Still Seem To Outpace Light

Doubtless you remember all the hubbub back in September when researchers at CERN observed neutrinos moving at faster than the speed of light. Of course, there were immediate calls for further testing, many scientists whole-heartedly expecting the next round of experiments to lay bare an error that could explain away the results. Nope. Retests are still showing neutrinos that are outpacing beams of light, even in follow-up tests specifically designed to eliminate some of the perceived inaccuracies of the first test.

One of the concerns, which was recently tested, had to do with the length of the proton pulses used to generate the neutrinos that made the original record-breaking run from CERN to Gran Sasso. I’m no scientographist, but the issue seems to be that in the original test, the proton bursts were 10.5 microseconds long, which is apparently sort of a long time. That being the case, it was tough to tell what stage of the proton pulse any given neutrino came from, creating a certain level of haziness in observed travel time.

In this recent follow-up experiment (one of many to come, I’m sure) the proton pulses were shortened to a mere 3 nanoseconds. For comparison, that’s 3 thousand times sorter than the original pulses. This allowed researches to get more accurate results regarding the travel time of particular neutrinos and, even with this increased accuracy, they still look like they’re beating the speed of light.

Granted, this is just one alternate experiment and there are many, many more to come in the future. There are caveats involving the GPS system used to track the times that need to be explored and, of course, every one is itching for an independent replication in a new location. For the time being however, this shows that if the faster-than-light neutrinos are due to a mistake, it probably wasn’t a really stupid one. It’ll be a long time before scientists will say that things even look promising, but right now, I think it’s safe to say they don’t look un-promising.

(via Nature)

Relevant to your interests

• The GPS tracking is still something that might explain the results away, but it’s hard to test
• But boy was it exciting when it first happened