Secondhand Science

“Neutrinos: never seen, never heard and there’s one behind you RIGHT NOW!”

Scary question: what do neutrinos, ninjas and Bigfoot have in common?

Even scarier answer: Almost everything.

For starters, neutrinos are shrouded in mystery. They were first predicted decades ago, but there’s a lot we still don’t know about them. What’s a neutrino’s mass? How fast do they move? How many types are there? Boxers or briefs? Do they like gladiator movies?

We know none of these things about neutrinos. Just like ninjas and Bigfoot.

Neutrinos are mysterious because they’re extremely hard to detect. They pass right through air, liquid, solids — even the earth itself. Neutrinos make no sound, give no advance warning and make only the slightest disturbance as they pass.

Sound like any feudal Japanese assassins or Sasquatches you know?

Paradoxically, though, neutrinos are basically everywhere. They’re created by processes including nuclear fusion, like in stars or supernovae or a really intense Dave Matthews Band gig. If you put your hand up to the sun, one trillion neutrinos will pass through it every second.

(Of course, if you put your hand anywhere else, they’ll still pass through it. You can put your hand under your butt in the dead of night, if you want; it won’t make a bit of difference.

Neutrinos don’t care. They do what they want.

Like ninjas. Like Bigfoot.)

This abundance does make neutrinos unique, though. If a trillion ninjas were nearby, you’d already be too dead to read this. And a trillion Bigfeet would stack ten thousand deep in the Montana woods, and someone would eventually notice the pile. Or the smell. Plus, there’d be a lot more idiotic beef jerky commercials on TV. Pretty hard to miss.

Neutrinos are hard to detect because they rarely interact. With no electrical charge, tiny mass and near-light speed, neutrinos are a pain in the ass to catch up to. Researchers only find them when one in a hugetillion pings off a molecule in an underground pool of laboratory water, or a detector array built into an Antarctic ice sheet. Short of running smack into the heart of an atomic nucleus, a neutrino could go undetected forever.

Like ninjas’ and Bigfeet’s long lost subatomic brother.

Of course, anything mysterious and spooky needs a nemesis. For ninjas, it’s pirates. Obviously. For Bigfoot, a zoom-lens Nikon. And for neutrinos, it’s the antineutrino — which some theories say is also a neutrino.

So, a particle that rarely interacts, can barely be seen and is also its own opposite. Maybe neutrinos are actually more like Batman. Or the Unabomber. The Batabomber? Possibly not.

Anyway, for such an antisocial particle, neutrinos get invited to an awful lot of physics parties. Scientists use the kind from supernovae as cosmic warning signals. Astronomers want to use them to “see” stars on the other side of light-blocking cosmic dust and gas. Neutrino property measurements could provide evidence for or against competing particle physics models. Neutrinos from the Big Bang could be some (or all) of the “dark matter” cosmologists have been trying to find. They can be used to monitor nuclear reactors. It’s possible (but not so likely — but still possible!) that neutrinos travel faster than the speed of light.

Yeah. They’re kind of a big deal.

In conclusion, neutrinos. A lot like ninjas, and also Bigfoot. And possibly Ted Kaczynski in a Batman mask. Only better.