If there's one result worth posting about from this week, it is the now famous (and in some circles infamous) exchange of neutrinos between CERN and OPERA, two European physics laboratories. Neutrinos are pretty cool as is, but what's really of interest here is what the neutrinos (muon-neutrinos, to be exact) appear to be doing on their trip from their creation at CERN to their detection at OPERA. They're arriving ever so slightly early: 60 nanoseconds early to be precise. For reference, quick calculation shows that light only travels 24 meters (just under 80 feet) in that time.
   How fast light travels is actually exactly what's at issue here; the neutrinos seem to be arriving at OPERA before light traveling along the same path would. If it is true this is the most significant find in physics for a century at least. For all practical purposes though, getting a result like this is a really good reason to check your equipment for obvious problems.
   Having a particle like a neutrino (which has a rest mass) not just match, but actually exceed the speed of light is a discovery rather akin to the earth actually being hollow. It goes against so much previous evidence that it's probably wrong.
   Pure incredulity isn't the only reason to be reserved. We know muon-neutrinos don't  normally travel faster than light; If they did, we'd have seen a bunch of them arrive well before the light from the recent Supernova in M101. Instead, everything hit us at roughly the same time. In addition, two experiments very similar to the one at OPERA (but admittedly at lower energies) didn't observe muon-neutrinos breaking the cosmic speed limit by and statistically significant amount.
   To their credit, the OPERA researchers seem to have taken every possible precaution to ensure that this result is real. They first observed this discrepancy almost six months ago, and since then, they've spent time making absolutely sure that they had the distance between the two labs almost exactly on (according to their paper, down to 20cm!), and making sure their timing systems were correctly synced up. They've repeated the experiment about 15,000 times with the same result, and they've take care to make sure there's no human bias sneaking in by blinding everything. Their arXiv paper is mostly a meticulous write up of their methodology and specific objections still haven't shown up.
   What's next? Verification. If other sites observe muon-neutrinos moving faster than light, than we have the biggest experimental physics discovery of the past century.  If they don't, the OPERA scientists missed something, and those 60 nanoseconds have been conjured out of the math. It'll be a some time before we know for sure.

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