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This fall, physicists in Italy published results suggesting that neutrinos travel faster than
light - significantly faster.
If true, this is really big news in physics, and of course most scientists are greeting
the results with skepticism… why, you might ask?
Well, they fly in the face of the well-established and experimentally supported theories of special
and general relativity.
And extraordinary claims require extraordinary proof.
So let's go visit the OPERA experiment in Italy and try to catch some neutrinos!
The kind researchers looking for the Higgs Boson at the LHC in Switzerland are already
crashing protons into each other to create explosions of subatomic particles – and
luckily some of those particles are neutrinos which fly straight through the earth's crust
to us here in Italy.
There are just three things that we have to do:
1) We have to catch the neutrinos, which, given that neutrinos will travel for roughly
2 years through lead before stopping, is an ambitious task.
But we can do it.
2) Once we have a neutrino, we have to figure out which proton collision it came from: imagine
blowing up a case of wine bottles, at night, and then having your neighbor call you up
and say "I caught a piece of glass!
Can you tell me which one it is?"
Well, we're that neighbor.
And 3) Once we figure out which collision a neutrino came from, we have to know exactly
what time the collision happened, AND exactly when we caught the corresponding neutrino.
And because the scientists in Switzerland are hundreds of kilometers away, we have to
use timing signals from GPS satellites in order to synchronize our clocks.
If we're off by even a microsecond, we'll get the speed wrong by a million km/hr.
So that's it!
Now that we've measured the neutrinos going faster than light, what next?
Well, because our results are so groundbreaking and our observations so hard to make, the
scientific community wants to be absolutely sure we didn't make any big mistake - so we
have to wait for other experiments around the world to confirm or refute our claim.
And this could take months or even years, so be patient…
And in the meanwhile, why not learn more about neutrinos?
Or how GPS works?
(click below to make a choice)