ARI SHAPIRO, HOST:
Physicists in Switzerland reported today that they'd conducted fresh experiments on antimatter. As NPR's Geoff Brumfiel reports, antimatter is extremely rare, and researchers want to know why.
GEOFF BRUMFIEL, BYLINE: You, me, your radio or smart speaker or whatever - it's all regular, old matter. So what then is antimatter?
JEFFREY HANGST: Antimatter - I think of it as kind of an evil twin of the stuff that makes up our everyday world.
BRUMFIEL: Jeffrey Hangst is a physicist at Aarhus University in Denmark. Think of it this way. Every type of particle in the universe has an opposite with opposite properties. And just like a bad movie, the twins can't meet.
HANGST: The antimatter matter can't exist in the presence of matter. That's where the science fiction stuff comes in.
BRUMFIEL: If matter and antimatter touch, they annihilate, turning into pure energy. Physicists can routinely measure this in the lab - negative electrons meeting positively charged antielectrons and disappearing in a flash. It all makes for some great episodes of "Star Trek."
(SOUNDBITE OF TV SHOW, "STAR TREK")
JAMES DOOHAN: (As Montgomery "Scotty" Scott) Antimatter pods are rigged to blow up the moment we go into warp drive.
BRUMFIEL: But in real life, the fact that matter and antimatter can't coexist is just, well...
HANGST: It's really just annoying to have to deal with something that you have to make and that the universe is trying to destroy (laughter) at every turning point.
BRUMFIEL: Producing even a handful of atoms of antimatter is tough. Physicists use a giant particle accelerator at a big lab called CERN to make antiprotons, which are the antiversion (ph) of protons, which make up the hearts of atoms. Hangst and his team slow those antiprotons down and then combine them with antielectrons. Smooshing them together is a really delicate business.
HANGST: We call its smerge (ph). (Laughter) It's a smooth merge.
BRUMFIEL: A lot of the antimatter ends up hitting the wall and disappearing in a flash. But every now and again, one antielectron ends up orbiting one antiproton. The result is an antiversion of the lightest element in the universe, hydrogen.
HANGST: Hydrogen is probably the thing we know best. We've been studying it forever. We really understand it.
BRUMFIEL: And Hangst hopes that by making antihydrogen and studying it, he can learn more about all antimatter. The big question on everyone's mind is why there's so much matter in the universe and so little antimatter.
HANGST: There aren't any good ideas about this.
BRUMFIEL: If Hangst found some difference between the twins, that might explain it. The latest measurements by his team are published today in the journal Nature. They have to do with how antihydrogen absorbs and emits light. So far, at least, Hangst says it looks like it behaves exactly the same as regular hydrogen.
HANGST: But this is really early days.
BRUMFIEL: He's planning more measurements for years to come. He says physicists - and all of us - have a lot more to learn about antimatter.
Geoff Brumfiel, NPR News.
(SOUNDBITE OF FOXYGEN'S "STAR POWER I: OVERTURE") Transcript provided by NPR, Copyright NPR.