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Primer: OK, It's Possibly Faster Than Light, But What's A Neutrino Anyway?

h5, Super-Kamiokande, a neutrino observatory in Hida City, JapanYou've heard by now a bunch of "superexcited stuff": about neutrinos and how they seem to be going...
October 2, 2011, 8:37pm
Super-Kamiokande, a neutrino observatory in Hida City, Japan

You've heard by now a bunch of superexcited stuff about neutrinos and how they seem to be going faster than light—violating the king theory of modern physics, relativity—in an experiment that has the particles racing through Europe underground. Neat. Awesome. Wait. What the fuck are neutrinos?

If you don't know much about neutrinos compared to, say, electrons and protons, you're to be forgiven. We're not made of them. They don't seem do a whole lot for us day-to-day here on Earth. They're the ultimate shy friend, that guy that can go to a party, spend three hours, and manage not to talk to anyone. In particle terms, they interact with so little that you can shoot them through the ground and they'll make it from CERN, Switzerland, to a detector at Italy's Gran Sasso underground lab without being affected by, or affecting, anything.


Part of that has to do with the neutrino being electrically neutral—yes, like a neutron. And a neutrino has so little mass that we haven't even be able to figure out what that mass even is. Neutrinos are also the most abundant particle in the universe. There's about 700 million of them for every one proton. Our bodies are bombed with them constantly, to the tune of tens of trillions of them passing through you per second. Every time nuclei come together or break apart, neutrinos are give off.

Carrots, red meat, and bananas, all naturally radioactive foods due to the element potassium, all kick out neutrinos. They're a natural product of radioactive decay.

Because neutrinos don't interact with much, they let us look at things that might be otherwise obscured. When a supernova collapses, the event is so energetic and dense that nothing but neutrinos are able to get out. Which means that neutrinos are all we can look at of the event. Eventually, neutrinos will let us look at the dense, obscured core of the Milky Way for the same reason. What's more, neutrinos should also provide us with ways of indirectly detecting dark matter. (They could even be dark matter!)

Neutrinos might also explain why we're even here existing right now. We shouldn't be is the thing. The universe should have been created with equal amounts of antimatter and matter, which would have annihilated and left nothing for us, or left nothing for us to become us. But there's an apparent asymmetry between antimatter and matter that allowed matter to exist for us to come about and ask what the hell?. Weird properties of neutrinos that allow them to oscillate between types ("flavors") and maybe even antiparticles and particles could tell us what's going on with more experiments. Which, even if faster-than-light neutrino observations prove to be bullshit, is about as impressive as it gets.


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