FTL Neutrinos Update (and updated again)

I have written here and here about CERN reporting that it had measured neutrinos travelling faster than the speed of light (FTL), contradicting Einstein’s theory of special relativity. Today there is another update.

One of the criticisms levied at the experiment (and one cited as a possible error in their calculations) is that the scientists used a relatively long pulse of neutrinos (lasting 10 microseconds), making it difficult to measure exactly when the neutrinos arrived. CERN scientists re-ran the experiment using streams thousands of times shorter (3 nanoseconds) with long pauses (524 nanoseconds) between. The idea is that with longer pulses, it can be difficult to measure when individual neutrinos left one location and arrived at another. Therefore, these shorter bursts can remove some of that uncertainty and be measured more accurately.

As described here and here, the researchers new results were consistent with the original experiments. But as Phil Plait points out here, the new experiments used the same timing device. So although the measurements might be more precise, they may be off by the same amount (think of it as measuring something twice with a bad ruler–consistent, but nevertheless incorrect results). He also points out that we still need to see replication of the experiment by other researchers.

Now, just to be clear, this is NOT, I repeat NOT, confirmation that neutrinos can travel FTL. It is merely a test of one of several possible causes of error in the original experiment. Nevertheless, this is a fascinating example of the scientific method in progress. Watch this space though. I’ll be sure to keep you updated as more experiments are resulted.

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