GUY RAZ, host:
There's a strange feature of quantum mechanics; that's the science of the very, very small. It's called quantum entanglement. Now, Einstein called it spooky, and it's now being used to teleport atoms from one location to another.
In a moment, we'll actually visit a lab at the University of Maryland's Joint Quantum Institute, where such experiments are happening. But first, a little lesson in quantum physics from Michio Kaku. He's a theoretical physicist and author, most recently of "Physics of the Impossible."
Welcome to the program.
Mr. MICHIO KAKU (Theoretical Physicist; Author, "Physics of the Impossible"): Glad to be on the show.
RAZ: Before we get to the teleportation, can you explain quantum entanglement for us?
Mr. KAKU: Well, it's one of the most bizarre features of the quantum theory. According to the quantum theory, everything vibrates. And when two electrons are placed very close together, they vibrate in unison. And then when you separate them, that's when all the fireworks start.
An invisible umbilical cord emerges, connecting these two electrons. And you can separate them as much as a galaxy, if you want. And if you vibrate one of them, then somehow on the other end of the galaxy, the other electron knows that its partner is being jiggled.
Now, Einstein though this was preposterous because it meant that in some sense, information can travel faster than the speed of light. Now, the information that travels faster than the speed of light is random information and hence, useless for communication. However, vibrations that travel slower than the speed of light can, in fact, be used to teleport objects - somewhat similar to what you see in "Star Trek," where you beam Scotty all over the place.
RAZ: Well, that's what I want to ask you. I mean, how does entanglement figure into quantum teleportation?
Mr. KAKU: It means that the information of one electron can be transferred to another electron. And in some sense, we are nothing but information. So if you can transfer the information content of an electron to another electron, then for all intents and purposes, it is that other electron.
RAZ: Explain what some of the practical applications of this might be, I mean, if this technology is developed.
Mr. KAKU: Well, the short-term applications are enormous in terms of computer technology. Realize that in 10, 15 years or so, computer power will exhaust the power of silicon. You cannot cram too many transistors on a silicon chip before you start to etch on individual atoms. At that point, we're going to have to go to quantum computers.
So in the future, your desktop computer will probably no longer compute on silicon; it'll probably compute on atoms. And this is going to happen in the next few decades.
The CIA is very much interested in this because you could crack any known code on the planet Earth with quantum computers.
Now, going farther into the future, perhaps we'll master the ability to teleport entire molecules, maybe even living objects as well.
RAZ: So let me just see if I've got this right. It's not actually teleporting one atom to another place. It's just sort of taking the information from that atom to another place.
Mr. KAKU: Right. However, we think that your identity of who you are is basically information. So, you know, we have a problem that you have to be destroyed in order to have your body teleported to the other side of the room.
So if you've now been destroyed and teleported, who is that person? They have the same memory, the same personality, the same jokes, everything - except the original was destroyed in the process of being teleported. So who is that other person there?
RAZ: That's Michio Kaku. He's a theoretical physicist at the City University of New York, and the host of "Sci-Fi Science" on the Science Channel.
Michio Kaku, thank you so much.
Mr. KAKU: My pleasure.
RAZ: Now, it could be a long, long time before we're teleporting human beings, but it is being done with individual atoms. And we sent producer Brent Baughman to the University of Maryland to see how it all happens. And Brent is in the studio with me.
What does that lab look like?
BRENT BAUGHMAN: So they have this giant, steel table there.
Dr. CHRISTOPHER MONROE (Joint Quantum Institute, University of Maryland): This one over here is where the teleportation experiment took place.
RAZ: And who's that talking?
BAUGHMAN: That's Dr. Christopher Monroe.
Dr. MONROE: I'm at the Joint Quantum Institute at the University of Maryland and the National Institute of Standards and Technology.
BAUGHMAN: He runs the teleportation experiments.
RAZ: Okay, so these atoms that they're teleporting, they're all in the same room, in that lab you saw?
BAUGHMAN: Like a few feet apart. And Dr. Monroe and his team actually spend most of their time creating the right conditions for quantum experiments. So for teleportation, that means they need to isolate two atoms into separate chambers.
Dr. MONROE: Through vacuum plumbing, we pump air out of chambers. We make lasers and propagate optical beams. We do a lot of machining, a lot of fancy electronics to control these lasers and so forth.
RAZ: They do all of this to isolate two atoms?
BAUGHMAN: Yeah. So here's how they do it. They have two chambers, just a couple of inches wide, a few feet apart. They put the atoms in there, and then they suck all the air out.
RAZ: That's not what it really sounds like?
BAUGHMAN: No, not really. Then they levitate each atom.
Dr. MONROE: So you just think of a magnetically levitated train tracks, if you want.
BAUGHMAN: And then they charge the atom with an electric field.
RAZ: So basically, what you then have is a levitating, supercharged atom.
BAUGHMAN: Right. Now, here comes the fun part. Once the atoms are charged, they shoot each one with a laser.
(Soundbite of laser)
RAZ: That's not what it sounds like.
BAUGHMAN: No, it's not.
Dr. MONROE: And something very special happens then. The atom emits a single photon, sort of a particle of light.
BAUGHMAN: And when those photons are released...
Dr. MONROE: They interact with each other, in a sense.
BAUGHMAN: So let's recap. Once they've vacuumed the chambers, levitated the atoms, charged them, and shot each one with a laser, they get one photon from each atom, and when those photons interact...
Dr. MONROE: Two atoms are now entangled.
RAZ: Just let me clarify something. It doesn't really sound like that, right?
BAUGHMAN: It actually doesn't make any noise at all.
RAZ: Okay, okay. But we so we've now got the invisible connection Michio Kaku explained. I get that.
BAUGHMAN: Right. And here, from here on out, it's kind of like hooking up a phone line. Now, they can send information from one atom to another.
RAZ: Okay, I'm still not clear here. How does this how does this work?
BAUGHMAN: Well, that's why quantum physics is kind of spooky. No one really knows why these two atoms can communicate information. But frankly, Christopher Monroe, at the University of Maryland, he says he doesn't think too hard about any of all that. And because he doesn't think too hard about it, he could actually make some real progress on the road to things like quantum computers and communication technology.
Dr. MONROE: We don't know where it's going. We don't know what it will look like 10 years from now. And that drives me every day because it's almost like playing the lottery, in a sense - very low probability that we're going to be able to make that breakthrough. But yeah, it's not zero.
RAZ: That's Christopher Monroe from the Joint Quantum Institute, at the University of Maryland. Brent Baughman is a producer on this program.
Brent, thanks so much.
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