Teleportation was long considered impossible because it violates the so-called uncertainty principle of quantum mechanics. As the principle goes, the act of measuring a tiny particle destroys it. So theoretically, an exact replica of a particle can never be made.
But in 1993 scientists showed a way around the problem by using a complex concept known as entanglement, an area of physics that Albert Einstein referred to as "spooky action at a distance."
Since then, numerous experiments using photons have proved that quantum teleportation is possible. Scientists have teleported quantum bits along more than a mile (1.6 kilometers) of fiber-optic wire inside laboratories.
The science is not new, said Mark Kuzyk, a physics professor at Washington State University in Pullman. But this is the first time "researchers have demonstrated that teleportation works in the kinds of real-life conditions that are found in telecom applications."
No Eavesdropping
The most obvious practical application for quantum teleportation is in cryptology. Scientists say quantum physics can provide a completely secure method of communication between two distant correspondents. Sending photons entangled in a quantum state makes it impossible for an eavesdropper to intercept a message.
"There is no copy [of the information], so there is nothing to intercept," Ursin said.
The problem, for now, is that the quantum technology only works over limited distances. Physicists are now laying the groundwork for so-called quantum repeaters. Used in regular communications, these devices would allow messages to be transmitted around the world.
Commercial applications remain far off. "But this is really the step toward a real-world implementation of a long-distance quantum teleportation protocol," Ursin said.
So what are the chances of developing a transporter that can beam people from one location to another, Star Trek-style?
"Nothing we do will help us build Scotty's apparatus," Ursin said. "The reason is very simple: A human body contains too much information to scan and build all replicas."
For a human to be teleported, a machine would have to pinpoint and analyze the trillions and trillions of atoms that make up the human body. Only recently have scientists taken preliminary steps toward teleporting even a single, whole atom.
For more teleportation news, scroll down to bottom.
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