The World's Largest Particle Accelerator Physicists are building a particle accelerator that will smash subatomic particles together with tremendous force. What they find may solve some fundamental mysteries about how the universe is constructed — IF everything works.
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The World's Largest Particle Accelerator

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The World's Largest Particle Accelerator

The World's Largest Particle Accelerator

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This is ALL THINGS CONSIDERED from NPR News. I'm Michele Norris.


And I'm Melissa Block.

Some pretty strange things have been rolling down the roads outside of Geneva, Switzerland, the past few years. Superconducting magnets that look like missiles, oversized pieces of brightly painted equipment, all headed to the huge physics lab known as CERN. When the parts get there, they disappear down shafts that reach 300 feet into the earth.

The work is all part of an $8 billion project. At it's heart will be the Large Hadron Collider, an enormously powerful particle accelerator. It's designed to recreate the energies that existed just after the Big Bang. And it could solve some fundamental mysteries of physics. But that's only if everything works.

NPR's David Kestenbaum went to Switzerland to check it out.

DAVID KESTENBAUM: To visit CERN these days is to feel very, very small in all sorts of ways. Take this recent morning: Technicians are standing around one of those deep shafts getting ready to lower what they say is the world's largest electromagnet. It's the size of a house. It can store enough energy to melt 18 tons of gold, and it's incredibly heavy. It dangles over the mouth of the shaft on four slender bundles of cable.

I talked to the safety guy who seems calm. His name is Christoph Schaefer, it says so on his hard hat.

What will happen if that fell on your foot?



KESTENBAUM: How much does it weigh?

SCHAEFER: Almost 2,000 tons.

KESTENBAUM: How is that compared to an airplane or something?

SCHAEFER: Oh, I don't know the - much less. It's much less, the airplane.

KESTENBAUM: It's the weight of five jumbo jets, or a little shy of the space shuttle with full tanks, or one-third of the weight of the Eiffel Tower. Anyway, it's going down the hole today, slowly. There are only seven inches of clearance.

The shaft is round, white-walled and well lit. The magnet is a gray metal cylinder that looks like it might be part of a spaceship. It sits inside a huge red octagon, layers of scientific equipment. The whole thing will be part of an even larger contraption, which, oddly enough, is designed to detect ultra-tiny subatomic particles. The detector is called CMS for Compact Muon Solenoid. It will sit far below our feet in a huge cavern.

MILAN NIKOLIC: Even though it was in New York subway.

KESTENBAUM: Milan Nikolic is with the University of California Santa Barbara.

NIKOLIC: So if you go to the 168th Street, IRT 1-9 station, it's bigger than that. And that's a huge cavern. I mean it's quite impressive. Like the size of the cavern is just amazing. It's actually in an underground river. We had to sink liquid nitrogen probes and like freeze the river around it to be able to lay the concrete structure down. I mean, it's a huge civil engineering project and the detector itself dwarfs anything I've ever seen. It's like a five-storey building. It's ridiculous.

KESTENBAUM: When it's all hooked up, the detector will have a special pipe running through it. If you leave the chamber, you can follow the pipe on foot into a tunnel. In five or six hours, you'll end up back where you started. It makes a 16-mile loop.

When the machine is running, particles will zip both ways around the loop and collide in the center of the detector with enormous energy, giving birth to a spray of new particles, maybe among them strange entities no one has seen before.

JIM VIRDEE: We hope to complete a journey started with Newton's description of gravity.

KESTENBAUM: This is Jim Virdee, physicist and spokesman for the CMS team.

VIRDEE: The source of gravity is mass. Mass is a very poorly understood concept where certain particles have certain masses. We don't know why. We hope to find the answer to this and understand the origin of mass, if you like.

KESTENBAUM: If that sounds like a peculiar question to ask and all this an elaborate way to find an answer. Well, I hear you. But that's how it is. If you smash things together, you get strange particles that aren't part of the everyday world: Z bosons, pi mesons, charm quarks. Some live only a very short time, but they are clues to the fabric of the universe.


KESTENBAUM: Behind Jim Virdee, the 2,000-ton magnet begins imperceptibly to disappear down the shaft. And even though it's 6:30 in the morning, dark and rainy, other physicists have dragged themselves out of bed to watch. Dan Green is the project manager for the U.S. contribution to this detector.

DAN GREEN: It's very - it's awe-inspiring, actually. This is the most excited I've been about physics for about 20 years. We expect to see things which are, you know, will change the way we view the universe. That only happens once or twice in a lifetime.

KESTENBAUM: No one really knows what the machine will give birth to. But the equations suggest weird things could be just around the corner - maybe dark matter, the invisible stuff that seems to hang around galaxies.

GREEN: I am personally hoping we make dark matter. Because it's kind of an embarrassment that, you know, we don't know what 95 percent of the universe is made out of by weight.

KESTENBAUM: Milan Nikolic is hoping they discover evidence of extra-tiny dimensions to space-time.

NIKOLIC: Because then I would have a job and stuff.

KESTENBAUM: And some theories say it's possible the collider will cause miniature black holes to appear. But, for now, what has appeared is a table of croissants and an urn of decent coffee, and more people with more immediate concerns.

NIKOLIC: It's (Unintelligible) to me. I hope it doesn't drop.

KESTENBAUM: Some people at the lab feel that these projects are pushing the boundaries of what can be achieved by humans financially, politically, organizationally. There are over 2,000 scientists working on just this detector. The list of names alone takes up more space than some research papers. And everyone speaks different languages. Fortunately, English is usually one of them.

Unidentified Woman #1: I'm from Spain, okay.

NORRIS: I am from Italy.

Unidentified Woman #3: I'm from Spain, Madrid.

Unidentified Man: From Sheffield, England.

KESTENBAUM: Could you say where you're from?

Unidentified Man #2: I'm from Germany.

Unidentified Man #3: I'm from Pakistan.

Unidentified Man #4: From Pakistan.

Unidentified Man #5: I'm from the Serbia, from Belgrade.

NORRIS: I come from Greece.

NORRIS: I am from Ecuador.

KESTENBAUM: You're the first Ecuadorian I've met.

Unidentified Man #7: Yeah, we are just few, less than five Ecuadorians and it's kind of difficult.

KESTENBAUM: It takes a whole day for the magnet to inch down the shaft. In the evening, people gather in the underground cavern. The detector hangs above us like a giant yo-yo. And for some reason everyone whispers.

It's a classic test of faith. On the one hand, everyone trusts the math that says this huge thing won't fall. On the other hand, no one wants to stick their head under it, though we do for a second.


KESTENBAUM: In a way, this whole project is a test of faith. People don't like to talk about it, but it is possible these experiments may not find much at all. It's possible that nature or God has been mean and put the final answers on the top shelf, out of reach. I ask one physicist how much time she's putting in - infinite, she said.

The experiment is supposed to start running this summer. But a lot of people, a lot of languages, a lot of pieces means a lot to go wrong. And this gargantuan detector, this is actually the little one. It has a much larger brother a few miles away. Its name is Atlas.


KESTENBAUM: Atlas is mostly in position. Workers are crawling over it like insects. Bob Staneck is a physicist from Argonne National Laboratory outside Chicago.

Does anybody ever get lost in there?

BOB STANECK: Oh yeah. Tell me about it.


STANECK: See, take a look around. There are some guys putting cables in or chambers or making connections. And you wonder, how the heck did they get there. And I want to go by that guy, for example. I ask the guy, how do you get there? And you've got to down over here, open up that door and come on up. And there are these little trap doors every now and then that you have to crawl up. And then to find your way back out, if you don't have a string attached to yourself it is sometimes a challenge. That's for sure.

KESTENBAUM: It will take years to fully analyze the data recorded by these machines. The accelerator will create collisions 600 million times each second - that's if the accelerator works as designed.

We leave the cavern and walk into what looks like a subway tunnel. Everything is suddenly quiet. This is what people call the ring, the particle accelerator itself. Thousands of magnets arranged like boxcars on a long, 16-mile racetrack. It's so long the tunnel seems almost straight.

Oh, yeah, you can see the curve here.

PETER LIMON: You can actually see the curve, that's right.

KESTENBAUM: This is Peter Limon, a physicist from Fermilab in Illinois.

LIMON: It's actually very relaxing to go walking down this way because there's nothing different. You know, you kind of get in I would call it a trance, but it's some kind of nice, relaxing feeling of just walking around in there.

KESTENBAUM: The tunnel is so long people use bikes to get around down here.

LIMON: This is the most amazing thing I've ever seen built. The complexity and the scale of this thing, I think, you know, it rivals pyramids.

KESTENBAUM: The pyramids long outlasted their builders. And one physicist here wondered if, thousands of years from now, a future civilization will find these strange tunnels and equipment buried in the ground.

David Kestenbaum, NPR News.

BLOCK: And at you can watch a video of the huge detector piece being lowered into an underground cavern. And you can learn all about Higgs particles and miniature black holes.

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