Captain James T. Kirk of the Federation Starship Enterprise would be proud; teleportation, once only a topic in the realm of science-fiction, is now a reality.
A team of physicists led by Eugene Polzik, of the Neils Bohr Institute in Copenhagen, recently announced in the journal Nature that they had, for the first time, teleported across two different states, moving a "quantum state" (a phrase which, in this context, simply means information describing very small particles) from a beam of light to a clump of cesium atoms.
At first glance, this doesn't seem particularly impressive (or coherent), nor does it seem to have anything to do with "Star Trek;" after all, what seems complicated about connecting light and matter? In a sense, we all do these every time we see a traffic light turn green, and then step on the gas, we're transmitting information between those two mediums. But this goes far beyond mere intersections, and rests upon fundamental properties of some of the basic units of the universe.
Quantum mechanics, the study of the very small, is based upon something known as the "Heisenberg Uncertainty Principle," which states that it's impossible to precisely know both the location and the speed of any subatomic particle; you can measure one of those variables, but not the other. Just as not being able to have their cake and eat it too was infuriating to French peasants, Heisenberg's observation was immensely frustrating to modern physicists, as it hampers their ability to fully comprehend the world around them. It also would seem to make it impossible to ever experimentally "move" these particles. In order to manipulate an object, you would seem to have to know both where it is and where it's going, just as catching a baseball requires you to know how fast it's moving, and where in the air it is at any given time.
But, as with all laws, there's an exception, and therein lies this column. In theory, it's possible to "entangle" two different particles, which means that they are so interrelated that something affecting a state, say, the position, of one, would also affect another state, such as the speed, of the other, and these relationships are perfectly correlated. This is similar to having a three-legged race: if I'm connected to you, and someone measures my speed, they also measure your speed, and if they measure your position, they know mine as well. It's a neat trick.
When these particles are separated, oddly enough, entanglement still holds, and it's possible to tell the state of one particle from the state of its corresponding pair, even if the two particles are miles apart from each other. In the past, researchers were only able to do this with two different particles of light, but now, they can do it with matter as well, a phenomenon given the name "teleportation."
These properties are not merely an intellectual curiosity, but could prove important to fundamental technological improvements in computers and communications. Most modern electronics, from iPods to cell phones, transmit information in binary form, and they use strings of ones and zeros to form Billy Joel songs, phone calls to your parents and the computer calculations from which Windows and Word are derived. These digits, however, can take time to be transmitted, and mistakes are sometimes made, leading to corrupt files and dropped cell calls.
But entangled particles avoid these problems. Remember, a change in one will be manifested, or teleported, to the other, and this change represents information, just as if it were ones or zeros. And since these particles can transmit information with much less interference than conventional means, it can lead to better, faster and more secure computers and communications devices.
This type of teleportation isn't quite the same as being able to beam myself from Providence to Poughkeepsie. But it eventually might just make it possible for me to make clearer, more secure phone calls to that city in New York, and can allow for computers that are faster and better than anything we can yet conceive, all the while helping physicists to better understand the complicated world around us.
And I rather think Captain Kirk, and certainly Mr. Spock, would approve of that.
Joey Borson '07 admits that his "Star Trek" knowledge makes him a Don Juan with the ladies.
