Doomsday Fears for a Particle Accelerator
ALISON STEWART, host:
You are listening to the Bryant Park Project from NPR News, online all the time at NPR.org/bryantpark.
RACHEL MARTIN, host:
It's a lab experiment that's been 14 years and eight billion dollars, that's billion with a B, in the making. It's called the Large Hadron Collider, and it's near Geneva, Switzerland, at a facility called CERN. It's the French acronym for the European Council for Nuclear Research, and it's the largest particle accelerator the world has ever seen.
If physicists at CERN have their way, one of the things it will be able to do is create tiny black holes that they can study. But that's exactly what two men are worried about. Walter Wagner and Luis Sancho have filed suit to stop scientists from turning the CERN collider on. Their fear?
That its operation could unleash a black hole that would basically swallow the entire Earth, and all of us along with it. So, how realistic is that, and how might it happen? Joining us now to explain is David Morgan, physics professor at Eugene Lang College in Manhattan, and friend of the BPP. Welcome back, David.
Dr. DAVID MORGAN (Physics, Eugene Lang College): Thanks. Thanks for having me back.
MARTIN: So, first we're going to wind it all the way back and talk a little bit about fundamentals. Explain to us. What is a particle accelerator?
Dr. MORGAN: A particle accelerator is basically a big machine that physicists build in order to smash particles together at really, really high velocities in order to see how they behave, and what comes flying out.
MARTIN: And what do you learn from that?
Dr. MORGAN: What physicists are trying to learn is something about the nature, the fundamental forces that govern our universe. Forces like the electrical force that holds atoms together, the strong force that holds nuclei together, and figure out how those forces work, and how they behave at various energies.
MARTIN: So, those are big questions. These machines, particle accelerators, really are at the foundation of some very big physics questions.
Dr. MORGAN: Yeah. You're really sort of - we're probing the fundamental structure of matter.
MARTIN: Let's talk about what these things look like. I actually visited CERN when I was a college student on a field trip, and it was a little bit overwhelming. I remember hearing some kind of vague explanation about what this big machine did, but it is physically large right, these things?
Dr. MORGAN: It is physically large. Basically, the Large Hadron Collider is contained in a tunnel that is 17 miles in circumference. So picture something about the size of a subway tunnel in diameter, and picture a round subway line that's about 17 miles around. So, every time the particles go around the accelerator once, they travel about 17 miles.
MARTIN: And just to clarify - CERN, there was already a particle accelerator at CERN. This is a new one that has just been built?
Dr. MORGAN: That's right.
MARTIN: Correct? Now, this new very large particle accelerator in Switzerland - we talked a little bit about some of the fears surrounding this thing, but why was it necessary? Why are scientists, why did they decide to build this?
Dr. MORGAN: What physicists are looking for at the LHC is really physics that's beyond what we call the standard model. In other words, particles and interactions that are things that we've never before observed in nature because we've never looked at nature at such a high energy. So, the hope among physicists is that we'll see something that we've never seen before.
Some particle, or some interaction, or some outcome that's unexpected, and there is a long sort of laundry list of things physicists hope to see, but I think many physicists would be even happier if they saw something they didn't expect at all.
MARTIN: Now, I know there's a long laundry list of things they expect to see, and I know that most of those would require a lot of explanation, but are there a couple examples on that list?
Dr. MORGAN: Sure, I can give a couple examples. One is a particle called the Higgs-Bozon, which physicists think is the particle that's responsible for why things have mass. In other words, in particle physics, there's no explanation for why an electron or a proton or anything has this property that we call mass, that it is hard to push it, and the idea is that the Higgs-Bozon is the particle whose interactions essentially give particles mass.
There's another set of particles called supersymmetric particles, which are sort of partners to every particle that we normally encounter around us. So, an electron has a particle called the selectron, and a quark has a partner called the squark, and these are particles that are postulated for various sort-of technical and mathematical reasons that a lot of physicists would like it if they existed, but we've never seen one before in the lab, so...
MARTIN: So, this accelerator can create the circumstances necessary to hopefully observe it.
Dr. MORGAN: Which is basically just a lot of energy. By Einstein's equation, E equals MC squared, if you get enough energy together you can create particles of matter. And because these particles of matter are more massive than any we've found before, we need a lot of energy in order to make them.
MARTIN: I want to talk about black holes. There is some speculation that this machine might be used to create small black holes. Now, why would someone want to create a black hole, and how would you even do it?
Dr. MORGAN: Well, a black hole is what you get if you take a whole bunch of matter and energy and put it in a very small space. So, usually when we think about black holes we think about astronomy where a collapsing star can create such a high density that it's so dense that light would be unable to escape from its surface. But I can make anything a black hole if I squished it small enough. I can make you a black hole if I squished you about down to the size of a proton.
MARTIN: You could make me a black hole?
Dr. MORGAN: Well, theoretically. It would require - we would have to stick you in the particle accelerator and get you going really fast to smash you down to that size. But the idea is with this particle accelerator, if we smash together two very small particles at a very high velocity, we are packing a huge amount of energy into a very small space, and that could create a teeny tiny little black hole.
STEWART: If one were to make a black hole on the radio, it might sound a little bit like what we are about to hear. NPR's esteemed science correspondent Robert Krulwich actually did a piece on this back in November 2006, in which he spoke with Professor Brian Greene from Columbia University.
ROBERT KRULWICH: It would, says Brian, be entirely possible to take, for example, an ordinary common watermelon and put it inside some incredibly powerful squeezing machine that's not yet been invented, that squeezes so fiercely that the watermelon would become denser and denser.
(Soundbite of pressure building)
KRULWICH: And so dense that at some point predicted by Einstein, the watermelon would change states and become...
(Soundbite of splat)
KRULWICH: A mini black hole.
Dr. BRIAN GREENE (Physics, Columbia University): Oh, yeah. Absolutely.
KRULWICH: Now, I know we made the sounds up there, but theoretically this is a real possibility?
Dr. GREENE: Oh, yeah. Absolutely.
KRULWICH: In fact, in the next decade, he says, teams of scientists will try to manufacture mini-black holes.
Dr. GREENE: And this is not just hypothetical. There is a new machine being built in Geneva, Switzerland, right now, called the Large Hadron Collider, and one of the things that may happen at the Large Hadron Collider is the creation of microscopic black holes in the collision between protons and protons. These will be tiny black holes, but black holes nonetheless.
MARTIN: Now, that was part of an NPR piece from November 2006. Fast-forward to today, and physicists are about ready to take that Large Hadron Collider in Geneva for a spin, they are about ready to start using this. And as we said before, there are some people out there who are concerned that this machine could create a mini-black hole, which could basically suck us all into oblivion. How realistic is that, David?
Dr. MORGAN: I don't think it's very realistic at all for a couple of reasons, one of which is the black holes that would be created are very, very tiny, which means they have a very, very small mass. Now, one the misconceptions about black holes is that they are these sort of magical sucking machines, that once you make a black hole it just sucks everything around.
A black hole just has a gravitational pull like everything in the universe has a gravitational pull. So, for example if I were to squish you down into a black hole right now, I wouldn't go flying across the studio and stick to you, because you still have the same mass that you had before. The gravitational pull is the same.
So, yes the Large Hadron Collider could make a teeny tiny little black hole, but the energy of this black hole would be about the same mass energy of a mosquito, and it has no more danger of this little black hole sucking up the Earth than a mosquito is in danger of sucking up the entire Earth with its gravitational pull.
MARTIN: So, let's talk specifically about the lawsuit, then. How much merit does this suit have? And what are the arguments being put forth?
Dr. MORGAN: I think it has very little. First of all, it should be noted that this same individual put forward a similar lawsuit to keep them from turning on the Relativistic Heavy Ion Collider, which is out on Long Island, and has been running for years, and last time I checked, Long Island is still there.
MARTIN: So, this is someone who has - he has some fear, let's just say.
Dr. MORGAN: Yes, and the other thing is while the Large Hadron Collider is going to create the sort-of highest man-made energies ever created in a particle accelerator, it's certainly not the most energetic thing in nature, or the most energetic thing to happen on the Earth. Our planet is bombarded by cosmic rays from space every day that are billions of times more powerful than the Large Hadron Collider.
So if there is any danger of a micro black hole being created to devour the Earth, it would have happened up in the top of our atmosphere sometime within the last four to five billion years.
MARTIN: You're not afraid. You're not living in fear.
Dr. MORGAN: I won't be losing any sleep over this.
MARTIN: David Morgan, physics professor at Eugene Lang College in Manhattan, thanks as always.
DR. MORGAN: Thank you.
ALISON STEWART, host:
Hold on there, whipper snappers. This black hole business isn't over yet. We want to get back to that piece by NPR's esteemed science correspondent Robert Krulwich that we just excerpted, because it helps explain one reason why the scientists in Geneva might be interested in creating tiny black holes.
The conversation between Krulwich and physics professor Brian Greene was actually about efforts to create a man-made universe. We've already heard that scientists are close to creating microscopic black holes. Get out your pens and take notes as Mr. Krulwich and Greene explain the next step in creating a man-made universe is to take a tiny black hole and expand it. Do tell.
Dr. GREENE: It then explodes.
(Soundbite of explosion and orchestral music)
Dr. GREENE: Roughly speaking.
KRULWICH: Now, this is the universe I was waiting for. So, how do you do this? Obviously you've inserted something or you've changed something to alter the physics of the little black hole, right?
Dr. GREENE: Yeah, exactly, and physics has to do with a strange feature of gravity that none of us have ever experienced, but the math shows us is true, and observations of space seem to confirm, and that is that gravity can actually be not only attractive, it could not only pull things together, it can also be repulsive, it can push things apart.
KRULWICH: And this force exists in nature?
Dr. GREENE: The repulsive side there is actually direct observational support for.
KRULWICH: So, it is there, and if you can learn to release this repulsive force theoretically you can hit a ball into the air.
(Soundbite of hitting)
KRULWICH: And instead of coming back down in to Earth.
(Soundbite of whirring)
KRULWICH: Instead, the space between the ball and the Earth would suddenly be filled with repulsive energy pushing out, pushing on two sharp elbows, pushing the ball further, and further, and further away from Earth as the space between gets bigger, and bigger, and bigger, so this force what it does, it creates space - so much space that it can turn a little black hole into a universe.
(Soundbite of orchestral music)
Dr. GREENE: Because the repulsive side of gravity is so powerful that it actually injects energy from gravity itself into the expanding space. So, from that point of view, all you need is the seed, and then gravity takes over and does the rest of the work.
KRULWICH: And right now there are scientists at Ben Gurion University in Israel, Yamagata University in Japan, Stanford University in California, who are trying to manufacture first a seed, the mini-black hole, and into that seed one day they hope to place a trigger to release this repulsive force and so create, unbelievable as it may seem, the first man-made universe.
MARTIN: So, I don't want to hear anyone complaining about not learning anything from the news ever again. That was NPR's esteemed science correspondent, Robert Krulwich.